What is a prime number

The number which can divided by 1 or itself is called Prime Number.Example: 2,3,5,7 etc. And 1 is neither prime nor composite number. 

A prime number is a whole number greater than 1, whose only two whole-number factors are 1 and itself. The first few prime numbers are 2, 3, 5, 7, 11, 13, 17, 19, 23, and 29. As we proceed in the set of natural numbers N = {1, 2, 3, ...}, the primes become less and less frequent in general.
 

Hi,
   Prime number is the number which has only 2 factor or the number which is divisible of the particular number. i.e 3 has factor 1 and 3.
regard
           Meritnation expert Harshwardhan