Q: Is 21,921 a Prime Number?
A: No, 21,921 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 21921 can be evenly divided by 1 3 7,307 and 21,921, with no remainder.
Since 21,921 cannot be divided by just 1 and 21,921, it is not a prime number.