Q: Is 21,638 a Prime Number?
A: No, 21,638 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 21638 can be evenly divided by 1 2 31 62 349 698 10,819 and 21,638, with no remainder.
Since 21,638 cannot be divided by just 1 and 21,638, it is not a prime number.