Q: Is 21,331 a Prime Number?
A: No, 21,331 is not a prime number.
A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 21331 can be evenly divided by 1 83 257 and 21,331, with no remainder.
Since 21,331 cannot be divided by just 1 and 21,331, it is not a prime number.