Prime number

A prime number is a number that can only be divided by itself and 1.

For example, 5 is a prime number. This is because 5 can only be divided by 5 and 1 and still remain a natural number.

The first 25 prime numbers follow...
 * 1) 2
 * 2) 3
 * 3) 5
 * 4) 7
 * 5) 11
 * 6) 13
 * 7) 17
 * 8) 19
 * 9) 23
 * 10) 29
 * 11) 31
 * 12) 37
 * 13) 41
 * 14) 43
 * 15) 47
 * 53
 * 59
 * 61
 * 67
 * 71
 * 73
 * 83
 * 89
 * 97
 * 101

1 is not a prime number since 1 is itself and has only 1 factor. Prime numbers contain 2 factors.