Interesting facts about Pi you may not know

How much do you really know about pi ? Here are some facts about pi that your math teacher rarely tells you.

Sure, you've heard about it in math class—likely sharing a pi joke or two —but this famous number has such a fascinating history that it even has its own holiday. Every year on March 14, math enthusiasts around the world celebrate Pi Day —a day dedicated to the infinite, irrational number that starts with 3.14. And one of the best ways to celebrate the day is to learn and share the most interesting, fun facts about pi !

What makes pi so special? Let's dive into some of the most surprising facts about pi —its history, its quirks, and why it continues to fascinate mathematicians and curious minds.

Interesting Facts About Pi

• Pi is part of Egyptian mythology.
• Humans have used pi for thousands of years.
• Experts know some tricks to remember pi
• Givenchy sells a men's perfume called Pi
• One pi calculation has dominated for nearly 1,000 years
• Pi Day is a relatively new holiday.
• Pi is a number that never ends.

Pi is part of Egyptian mythology.

The Egyptians believed that the pyramids of Giza were mathematical wonders, built on the principles of pi. What’s the interesting fact about this pi relationship? Well, imagine this: The height of each pyramid coincides with the circumference of its base, just like the notch between the radius of a circle and its circumference. No wonder the pyramids are one of the seven wonders of the world!

Humans have used pi for thousands of years.

Pi (the Greek letter π, pronounced like “pie”) is the ratio of the circumference of any circle to its diameter, explains math teacher Steven Bogart in Scientific American. It equals about 3.14. No matter how big a circle is, its circumference will always be 3.14 times larger than its diameter. The ancient Egyptians and Babylonians discovered this constant more than 4,000 years ago and used it in calculations. In the 18th century, mathematicians named the number “pi.”

Experts know some tricks to remember pi

How does one memorize a string of 100,000 random numbers? Most record keepers (or just enthusiasts) use an association technique. They group small groups of numbers together and memorize them: 14, then 15, then 92, then 65, etc. Or they might think of each set of nine digits as a phone number and memorize them that way.

Another strategy is to pair each number or small group with a word, then create a story from those words. Another method is spatial visualization, in which you visualize a familiar place and then assign each number to different locations in that place. To recall them, walk through the space and see the numbers as you go.

Givenchy sells a men's perfume called Pi

Here's perhaps one of the most interesting facts about the number pi : This French luxury perfume house has a men's fragrance called Pi. The website describes it as "a woody and seductive fragrance for the man who wants to push his limits."

One pi calculation has dominated for nearly 1,000 years

Zu Chongzhi was a 5th-century Chinese mathematician and astronomer. He cracked pi, squeezing it down to a sweet seven decimal places—between 3.1415926 and 3.1415927. This calculation held the title of the world's most accurate for 1,000 years, reigning supreme until the 14th century.

Pi Day is a relatively new holiday.

In 1988, Larry Shaw of the Exploratorium science museum in San Francisco began observing March 14 as Pi Day. March 14 is also the birthday of Albert Einstein. By 2009, the celebration had grown so large that Congress passed a resolution to officially designate the day. The resolution stated: “The House of Representatives supports the designation of ‘Pi Day’ and its worldwide observance… encouraging schools and educators to observe the day with appropriate activities to teach students about pi and engage them in the study of mathematics .” In 2010, Pi Day got its own Google Doodle.

Pi is a number that never ends.

One of the most well-known (yet still surprising) facts about pi is that it is an irrational number. It cannot be expressed as a fraction, it does not end in a repeating pattern (like the decimal expressions 1/3, 0.33333 …, where the number three repeats forever), and it does not end after a certain number of decimal places (like 3/4 or .75). To date, pi has been calculated to 100 trillion digits, courtesy of Google Cloud.