(NBC) - Happy Pi Day! The annual celebration, held every March 14, is your chance to pay tribute to the most famous constant in math and physics: the number you get when you divide the circumference ...

Pi Approximation Day falls on July 22 (written as 22/7 in the day/month date format). It commemorates the common approximation of the mathematical constant π as 22⁄7, which dates back to Archimedes ...

22 digits. The reason I remember this is because in 7th grade, my math teacher had a banner that circled the entire room with pi to a great many digits on it. Since I was bored a large portion of the ...