20 Things To Know About Pi Day

Happy Pi Day, everyone!

I don’t know about you, but I always enjoy a good date that has significance. Dates like 11-11-11, 10-01-10 and 7-9-79 are fun, but March 14th always tops my list! Maybe I’m a geek. Maybe I just like pie.

Either way, today is Pi day! We’re celebrating with the handy infographic below, which offers us a whole bunch of fun facts about Pi. Get ready – there’s lots here that you probably don’t already know (unless you are a math teacher, and then you have an unfair advantage!) Keep reading to learn more.

Visualizing Pi

  • The decimal representation of pi has been computed to more than a trillion digits
  • Pi can be estimated by dividing the circumference of any circle by its diameter
  • Pi has about 64 billion digits
  • If you recited them without stopping, it would take you about 133 years
  • The world record holder memorized over 44,000 digits of pi (which took over 9 hours to recite)
  • Ancient mathematicians knew that the ratio of circumference to diameter was slightly more than 3
  • The earliest reference to pi is an Egyptian papyrus dating from about 1650BC by a scribe named Ahmes
  • Pi was discovered by Archimedes (He was Greek)
  • Archimedes took a polygon with 96 sides and inscribed a circle inside the polygon to visualize pi
  • All of the digits of pi can never be fully known
  •  A professor at the University of Tokyo took 116 hours to compute 6,442, 450,000 decimals of pi
  • The decimal representation of pi truncated to 11 digits is accurate enough to estimate the circumference of any circle that fits inside the earth within an error of less than 1 millimeter
  • There is no 0 in the first 31 digits of pi
  • At 39 digits, pi can estimate the circumference of any circle within the observable universe with precision comparable to the radius of a hydrogen atom
  • The Feynman point is at position 763, where there are six 9s in a row
  • No simple base 10 pattern in the digits of pi has ever been found
  • 2 pi in radians form is 360 degrees
  • Thus, pi radians is 180 degrees, and 1/2 pi radians is 90 degrees
  • The first to use pi definitely to stand for the ratio of circumference to diameter was English writer William Jones
  • The symbol for pi entered into use in 1737


pi info