The number Π is pretty amazing!

Of course, it what you get when you divide the circumference of any circle by its diameter. Moreover, it useful for measuring angles in such a way that the derivative of the sine function is the cosine function. And, yes, it is an *irrational* number, so that its decimal expansion is not a repeating sequence of digits. Sure, all of these things are interesting, but not amazing.

What *is *amazing is that the number “e” raised to the power “Πi” is -1 and that the probability that two randomly selected positive integers are relatively prime is 6/Π^2! I mean, what’s up with that?!?!? What do those things have to do with circles anyway? It seems as if the geometry of circles must somehow be hiding behind the very structure of the numbers!

Another thing that is amazing is how much people love the number Π! How many numbers have their own holidays? Zero and one may deserve them, but Π is the only number I know with a holiday. Every March 14th is “Pi Day”. And it is coming up soon.

If you want to celebrate, or just want to learn more cool stuff about this intriguing number, visit Pi Across America. For example, you can go there to view the first 200 million digits and search for your favorite sequence. (FYI “2014” first appears 3,133 digits in, not counting the leading 3.)

Happy Pi Day, everyone!