What is a prime number?

A number greater than 1 that has no divisors other than 1 and itself. Examples: 2, 3, 5, 7, 11, 13...

No. By convention, 1 is neither prime nor composite.

How many primes are there?

Infinitely many. Euclid proved this around 300 BC. The largest known prime (2024) has over 41 million digits.

Last Updated: April 13, 2026

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