Q: Is 21,138 a Prime Number?
A: No, 21,138 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 21138 can be evenly divided by 1 2 3 6 13 26 39 78 271 542 813 1,626 3,523 7,046 10,569 and 21,138, with no remainder.
Since 21,138 cannot be divided by just 1 and 21,138, it is not a prime number.