Five Hidden and Interesting Facts about Pi π
5 Hidden Facts Everyone should know about Pi π : Here, we will discuss five special facts about Pi (π) that we must need to know. Maximum of us actually donot know about these facts of pi. That is why we have renamed these facts as hidden facts. Study the Complete post to know about the five Special hidden facts about pi now. Firstly, before knowning the facts, let us know some basic information about pi bellow.
What is Pi (π) ?
Pi (π) Symbol :
Simply, Pi is a Mathematical constant. Symbolically, it is denoted by π ( which is the symbol of Pi ), which is a Greek letter. There is many more formulae exists related to Pi (π) in Mathmatics and Physics basically. The Mathematical value of Pi (π) is 3.14 or 22/7. In geometrical use of π represents 180°. Pi π is an irrational constant. Which means, this can not be expressed as a fraction.
Definition of Pi (π)
Pi is denoted by the Greek letter π and is defined as the ratio of the circumference to diameter of a regular circle. In other words, the ratio which is made by the circumference and diameter of a unit radius circle, is 1 pi (π).
History of Pi (π):
Who discovered pi in maths for the first time?
The first determination of the value of pi π was done by the greatest Mathematican in the world – Archimedes around 287 to 212 BC. After all, He assumed the area of a normal circle by using the pythagoras theorem to find the value of the areas of two regular polygons. Firstly, the Polygon which is inscribed within the circle. Secondly, The Polygon within which the circle was circumscribed.
The Greatest Mathematican and Scientist Archimedes knew that he could not find the exact value of π but, he can find the approximate value. Thus, He saw that the actual area of the circle lies in between the areas of the both polygons that he assumed which gave the uper and lower approximate value of the area. In this way, from this experiment, Mathematican Archimedes gave a hints that the value of π lies between 3.14285714 and 3.14084507.
After Archimedes, Zu Chongzhi around 429 to 501 BC, who is a brilliant Chinese mathematician, also completed some experiments to find the value of π and gave some more hints. In this way, the practical use of Pi (π) was firstly began from 17th century. After which, the popularity of the use of π increased around the world in 1737 – 1740 approximately.
ALSO READ: A TO Z TRIGONOMETRY FORMULAE TABLE & IDENTITIES LIST (CLICK HERE) 
Five Hidden and Interesting Facts about Pi π
Fact1: 3.14 and 22/7 are NOT THE ACTUAL VALUE OF Pi
Yes, Neither 3.14 nor 22/7 is the actual value of pi π. These are only some primary approximation of pi. We can not find the exact and total digits after the decimal place of pi. We can remember the value of pi upto some digits. But, for Mathematical calculations, for easy use, the value of pi is assumed as 3.14 or 22/7. The value of Pi upto 50 digits after the decimal is given below, check it out.
The first four approximate fraction of pi are 3, 22/7, 333/106 and 355/113. Out of these four values, 22/7 is considered as the most usefull fraction for our practical Mathematical uses.
Fact2: Do You Know About The Pi Day?
Did you listen about Pi or pie Day before? If No, It is surprise, and if Yes, now you will know everything about the Pi day here – when and why people celebrate it, when it was started etc.
Every year, on 14 March, people all around the world are celebrating the pi day. The exact timing of celebration is 1:59:00 on 14 March. The only reason behind it is the first 6 digits of the value of π, which is 3.14159. The month march is 3rd month of a year, which represents the first digit “3”. After which, 14 is the exact date and the other 3 next digits represent the celebration time.
Pi day was celebrated in 1988 for the first time Larry Shaw at San Francisco ExploraTorium. In this way, on the 12th March 2009, the US decided to celebrate 14 March, 2009 as National Pi Day. Finally, in the year 2019, on the 40th GENERAL CONFERENCE of UNESCO, the committee decided to celebrate 14 March as the INTERNATIONAL PI DAY or INTERNATIONAL MATHEMATICS PI DAY.
In addition to this, the whole “March” month of the year 2014 was celebrated as Pi Month and in the next year 2015, the 14th March was celebrated as super pi day. Please refer to the below chart for Complete pi day summary.

Celebration Styles
Main celebration style of the pi day are eat Pie (Pizza) and Discussing about various facts of pi. On this date, various educational institutions organised educational meet and discuss about pi all around the earth.
Fact3: Indian Guinness Book Record on Pi
Can you remember 100 different digits without rendomize them? Can you remember even 50?
But, we know that Indians are unique, and you will shocked that, one normal people from INDIA remembered 70,000+ digits of pi π. Yes, It is 100% true and that is why he won one of the best Guinness Book Record.
The man Suresh Kumar Sharma from India memorized upto 70,030 digits of pi (π) on 21 oct, 2015. It tooks a moment of 17 hours and 14 minutes for him.
If you are an Indian, you can also proudly say that, the next one, who memorized upto 70,000 digits of pi is also from INDIA. Rajveer Meena from Mohocha village in Swaimodhapur district of Rajasthan memorized 70,000 digits of pi after the decimal place. In this way, Beating a Chinese record, Rajveer won the Guinness Book World Record for memorized and reciting 70,000 digits of pi in 9 hour and 27 minutes on 21 March, 2015 and he was awarded on October 1.
List of First 5 Guinness Book World Record for memorized and recite the most digits of pi is given below. Source: CLICK HERE
Name  Country  Digits  Recite Timing  Date 
Suresh Kumar Sharma  INDIA  70,030  17 Hrs, 14 Min  21 Oct, 2015 
Rajveer Meena  INDIA  70,000  9 Hrs, 27 Min  21 March, 2015 
Chao Lu  CHINA  67,890  24 Hrs, 4 Min  20 Nov, 2005 
Sudhir Dwivedi  INDIA  45,000  6 Hr  25 March, 2013 
Krishan Chahal  INDIA  43,000  5 Hrs, 21 Min  19 June, 2006 
Hiroyuki Goto  JAPAN  42,195  —  18 Feb, 1995 
Challenge Yourself
Do You Think that You can beat them? Ohh! That’s cool. Try to memorize the digits of pi as maximum as you can and simply apply online for Guinness Book Record. To know the First 1 Million digits of pi, Please CLICK HERE and try now.
Fact4: Why is The Value Of Pi 180°?
Do you know, π also have a geometrical value, which is 180°. Value of 2π is the complete angle made by a point, that means 360°.
This is because, one pi is the ratio of the circumference to the diameter of a unit radius circle. Diameter is a straight line. And we know that the angle made by a straight line is 180°, which is also know as linear angle. That is why, geometrically, the value of π in degree is 180°.
Refer to the below figure for Complete concepts:
Fact5: Do You Know The Alternative name of Pi (π) ?
Did you know that Pi (π) is also known as Archimedes Constant.
Archimedes Constant is the alternative name of pi π. Pi is denoted by π, is a small Greek letter, a Mathematical constant and the greatest Mathematican Archimedes tried to find the approximate value of pi for the first time. Using Pythagorean theorems in polygons, he succeeded to find a approximate limit for the value of π.
Since, Archimedes tried to find the value of pi for the first time and also he succeeded a little bit, that is why this irrational Mathematical constant is also known as the Archimedes’ Constant.
ALSO READ: ALL ABOUT COPRIME NUMBER YOU MUST NEED TO KNOW (CLICK HERE) 
Pi π is an Irrational Number, Why?
We have studied about Pi a lot. We aare often discussing that pi is an irrational constant of Mathmatics. But why?
To get the reason, we need to turn back to the definitions of rational and irrational numbers.
Which type of numbers are known as irrational number? To get the answer, we need to know what is Rational number. Well! Every single Number, that can be expressed as a well fraction, where both numerator and denominator are intergers and the denominator never be zero, is called a Rational number. Opposite to this, are the irrational number. Which means, if we cannot express a number in well fraction, then that number is known as irrational Number.
Pi π is a number which decimal expansion is infinite and also nonrepeating ( π = 3.14159….). And, a number, whose decimal fraction is nonrepeating and infinite, is always irrational. That is why π is an irrational Number. Note that, 22/7 and 3.14 are just approximated value of π, are not the actual value of π.
Opportunity from Pi π
Yes! You are listening the truth. If you are assured that you can memorized more than 70,000+ digits post decimal of the value of Pi π, and can recite them, you can apply for Guinness Book World Records.
This is impossible to listen, but not for some people. You may be one of them. Ask yourself, be assured, if you can, then you can APPLY ONLINE for Guinness Book World Records. If you really succeed, your name will be listed in the GUINNESS BOOK RECORD for MEMORIZED THE VALUE OF PI π. You can try it, grab the list of the value of pi upto 1 Million digits below.
Value of Pi π upto 50 Decimal Digits
Value of pi π upto 50 digits post decimal is given below. Try to remember these digits if you can and have fun. Below is the expansion
3 . 1 4 1 5 9 2 6 5 3 5 8 9 7 9 3 2 3 8 4 6 2 6 4 3 3 8 3 2 7 9 5 0 2 8 8 4 1 9 7 1 6 9 3 9 9 3 7 5 1 0 
Value of Pi π Upto 1 Million Decimal digits
Mathematicans already calculated the exact decimal expansion of pi π in more than 1 milion digits. You will shocked that, some advanced computer programming engine can calculate the value of pi more than 22 trillion digits. It is pretty amazing right?
Okay, Here you can get the list of Decimal expansion of the value of pi π by click below button:
Pi Upto 1 Million Digits (Check here)
Use Of Pi π
We have learnt about pi π. Now, let us discuss some most common use of the constant pi π. Pi is basically used in many more Mathematical and physical formulae. Some of the special formulae, where we use pi are given below.
Circumference of Circle  2πr 
Area of Circle  πr² 
Are of Cylinder  2πr(r+h) 
Volume of Cylinder  πr²h 
Area of Cone  πr(r+l) 
Volume of Cone  1/3 × πr²h 
Area of Sphere  4πr² 
Volume of Sphere  4/3 × πr³ 
So, there are some of the basic formulae where we have used π as a constant.
Relationship between Pi and Gravity
Interestingly, There is a small relationship between the constant g – acceleration due to gravity and Pi – the Archimedes Constant. Let me clear by following maths:
g = 9.8 m.s² right?
Now we calculate its square root,
√g = √9.8 = 3.13… ~ 3.14 = π
That means, The square root of “acceleration due to gravity” is approximately equal with the value of pi π. Interesting, right?
Final Word
Hope, you have understood all the concepts, statements that we want to say through this post. You have just knew some most important facts about pi which are almost unknown by maximum people. Please share these valuable lacture with your best friends and relatives.
After all, pi is a very interesting Mathematical constant. We can get a very big chapter regarding pi. We can play with pi. History, definitions, facts are really amazing. We all should know about pi clearly, Completely. We have just tried a little to provide the fun of pi with our readers. Hope, these interesting facts really help a lot to my reader friends. Thanks for reading the article. Please share and hit the like button below. Also please read A to Z Trigonometry formulas table and identify list which will really help you. Thanks!
Frequently Asked Questions and Answers
Q. What is pi π ?Answer: Pi is an irrational Mathematical constant having approximate value 3.14 or 22/7 
Q. What is Archimedes Constant?Answer: Pi is known as Archimedes Constant. 
Q. When is the international pi day celebrated?Answer: 14 March Every Year. 
Q. What is the exact value of Pi?Answer: It is very difficult to find. Even computer programming can provide only upto some trillion digits. I mean, value of pi is a non repeating infinite decimal number. 
Q. Pi is rational or irrational?Answer: Pi is a irrational constant. 
Q. Who is Suresh Kumar Sharma?Answer: Suresh Kumar Sharma is a Guinness World record winner for memorizing 70,030 digits of pi. 
Q. Pi is irrational, but 3.14 and 22/7 are Rational, why?Answer: π = 3.1415926… which is non repeating infinite decimal number, so it is irrational. But, 3.14 is a finite decimal places Number and 22/7 is a well fraction. So, these two are Rational number. Note that 3.14 and 22/7 are just approximate value of π and not the actual value. 
Q. Who discovered Pi in Maths for the first time?Answer: The Greatest Mathematican and Scientist – Archimedes. 
Q. What is the meaning of Pi or Definition of Pi.Answer: The ratio of circumference to its diameter of a unit radius circle. 