Pi Day: 7 interesting facts about the most famous number in mathematics | Main stories

You can search for the first 200 million digits of pi Search for Pi a site maintained by David Anderson, a professor of computer science at Carnegie Mellon University in Pittsburgh.

2. Pi is ancient.

Although this number was not called pi until the 18th century, the numerical relationship between the diameter of a circle and the circumference has been thought of since antiquity.

In the second millennium BC. the Babylonians used 25/8 for pi (equivalent to 3.125), while the Egyptians are believed to have used 256/81 (equivalent to 3.160).

In a couple of passages from the Bible (1 Kings 7:23 and 2 Chronicles 4:2) the altar in King Solomon’s temple is called “10 cubits from edge to edge‘, while ’30 cubits encircled it round about’ – dimensions which seem to give the value of what we now call pi equal to 3.

The symbol π was first used to denote the ratio of a circumference to a diameter in 1706 by the Welsh mathematician William Jones. But it did not gain popularity until the Swiss mathematician Leonhard Euler adopted its use in the 1730s.

3. We used computers to calculate Pi with over 22 trillion digits.

In 2016, Swiss scientist Peter Trueb used a computer with 24 hard drives and a program called y-cruncher to calculate the pi number with more than 22 trillion digits, the current world record for counting pi. If you read one digit every second, it would take you just under 700,000 years to read all those digits.

4. People memorized huge parts of the number pi.

Mathematicians have been competing unofficially since at least the 1970s memorize as many digits of Pi as possible. In 2015, Suresh Kumar Sharma, a former vegetable vendor from Jaipur, India (now a memory coach), set a world record by successfully reading over 17,000 digits of Pi—a feat that took him 17 hours to accomplish.

The US record belongs to Mark Umila from the suburbs of Philadelphia, who read more than 15,000 digits of Pi in 2007.

Umile said he memorized the numbers by writing them down and then reading them out loud into a tape recorder — and listening to the recording over and over again. He said it was nice to be able to use his “sliver of Asperger’s” — a condition he once found debilitating — to start “successful work that has benefited my life and inspired others.”

5. Pi has a bit role in many books and movies.

The protagonist of Carl Sagan’s 1985 novel Contact, astronomer Eli Arroway, searches for evidence of extraterrestrial civilizations by listening for signals from space, and later searches for hidden patterns in the numbers pi (the latter storyline was cut from the 1997 film version).

Fans of the original Star Trek series may remember the 1967 episode Wolf in the Pen, in which Spock tricks an evil computer by telling it to calculate pi down to the last digit. And in Alfred Hitchcock’s 1966 Cold War thriller Torn Veil , a secret network of agents helping defectors escape the Soviet bloc is codenamed “π.”

6. Even rocket scientists need a little more than a dozen decimal places.

Although we know the trillions of Pi, we don’t really need them. Even NASA engineers round pi up to 15 decimal places when calculating interplanetary trajectories. In fact, if you were trying to calculate the size of the observable universe, using the 39 digits of pi would give you an answer no larger than the width of a hydrogen atom.

7. There are many other reasons to celebrate March 14.

March 14 is not only Pi Day, but also Albert Einstein’s birthday. I physicist Stephen Hawking — considered by some to be Einstein’s intellectual successor — died on March 14, 2018.

Other Pi birthdays include composer Johann Strauss, actors Michael Caine and Billy Crystal, music producer Quincy Jones and Apollo 8 astronaut Frank Bormann.