Fascinating Facts Behind the Mystery of Pi [2025]

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Facts about pi you don’t want to miss

Pi is a mathematical mystery that has captivated people for thousands of years. There’s even a holiday dedicated to this mystery—Pi Day, which falls on March 14 every year. People all over the world celebrate Pi Day in numerous ways, from cracking Pi Day jokes to learning more about the never-ending number. And when it comes to learning, you’ll feel smarter than ever with these interesting facts about pi below.

Ahead, you’ll uncover all sorts of tidbits, from the history of how pi got its name to the pi-related record breakers in the Guinness World Records. You’ll also see why this ancient mathematical constant gets an annual celebration—one that’s growing every year. So how many pi facts do you think you know? Read on to unlock parts of the mystery.

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Pi is part of Egyptian mythology

Egyptians believed that the pyramids of Giza were like math marvels, built on the principles of pi. The fun fact about this pi connection? Well, imagine this: The height of each pyramid concurs with the perimeter of its base, just like the groove between a circle’s radius and its circumference. No wonder the pyramids are one of the seven wonders of the world!