Check if a number is a prime or a composed number.
List all prime numbers up to 10 000.
If a number is prime you can see all the prime divisors for it.
Works with numbers up to 9223372036854775807.

A prime number is a natural number greater than 1 that has no positive divisors other than 1 and itself. A natural number greater than 1 that is not a prime number is called a composite number.