Why is 1 not considered a prime number?

Or, why is the definition of prime numbers given for integers greater than 1?

**Answer**

One of the whole “points” of defining primes is to be able to uniquely and finitely prime factorize every natural number.

If 1 was prime, then this would be more or less impossible.

**Attribution***Source : Link , Question Author : bryn , Answer Author : Justin L.*