Math & Numbers Facts for Kids

The number zero wasn't used in math until around the 5th century — before that, there was no way to write "nothing."

A googol is a real number — it's a 1 followed by 100 zeros. Google was named after it (with a different spelling).

Pi (3.14159...) has been calculated to over 100 trillion digits, and it never repeats or ends.

Every odd number, when spelled out in English, contains the letter "e."

A shuffled deck of cards has never been in the same order before — there are more possible arrangements than atoms on Earth.

111,111,111 × 111,111,111 = 12,345,678,987,654,321 — a perfect number palindrome.

In a room of just 23 people, there's a 50% chance two people share the same birthday — this is called the Birthday Paradox.

The Romans had no symbol for zero in their numeral system — that's one reason Roman math was so tricky.

The abacus, one of the oldest calculating tools, is still used in parts of Asia today and can be faster than a calculator!

In real-world data, the number 1 appears as the first digit about 30% of the time — this is called Benford's Law.