2 only divides by 1 and 2          2 is a prime number
3 only divides by 1 and 3          3 is a prime number
5 only divides by 1 and 5          5 is a prime number
7 only divides by 1 and 7          7 is a prime number

11 only divides by 1 and 11       11 is a prime number
13 only divides by 1 and 13       13 is a prime number
17 only divides by 1 and 17       17 is a prime number
19 only divides by 1 and 19       19 is a prime number

23 only divides by 1 and 23       23 is a prime number
29 only divides by 1 and 29       29 is a prime number

31 only divides by 1 and 31       31 is a prime number
37 only divides by 1 and 37       37 is a prime number

41 only divides by 1 and 41       41 is a prime number
43 only divides by 1 and 43       43 is a prime number
47 only divides by 1 and 47       47 is a prime number

53 only divides by 1 and 53       53 is a prime number
59 only divides by 1 and 59       59 is a prime number

and so on