Is "111" a prime number?

The number 111 is not a prime number. For a number to be considered a prime number, it cannot be divided by more than just itself and the number one. The number 111 is divisible by three and 37.

An example of a prime number would be the number 53. The number 53 is a prime number because it is only divisible by itself and the number one. One way to check if a number is prime is to see if it is divisible by three. To check if a number is divisible by three, simply find the sum of the digits of the number in question. The number 234 is not a prime number, because 2+3+4 = 9, which is divisible by 3.