# Which of The Following is Not a Prime Number?

**Answer: (1) 51 **

**Explanation:-
**51 is not a prime number because it is divisible by 3 & 17 but rest are the prime number. They are not divisible by any number.

Hence, the answer is (1) 51.

**Answer: (1) 51 **

**Explanation:-
**51 is not a prime number because it is divisible by 3 & 17 but rest are the prime number. They are not divisible by any number.

Hence, the answer is (1) 51.