Primes

A prime number is a natural number greater than 1 that has no positive divisors other than 1 and itself. Primes are the building blocks of the integers: every integer greater than 1 is either prime or a product of primes.

Key features

• A prime has exactly two positive divisors: 1 and itself.
• 2 is the only even prime; all other primes are odd.
• There are infinitely many primes.

Examples:

2, 3, 5, 7, 11, 13

Further reading

• Primes on Wikipedia
• Primes on OEIS