Q: Is 21,376 a Prime Number?
A: No, 21,376 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 21376 can be evenly divided by 1 2 4 8 16 32 64 128 167 334 668 1,336 2,672 5,344 10,688 and 21,376, with no remainder.
Since 21,376 cannot be divided by just 1 and 21,376, it is not a prime number.