Q: Is 21,243 a Prime Number?
A: No, 21,243 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 21243 can be evenly divided by 1 3 73 97 219 291 7,081 and 21,243, with no remainder.
Since 21,243 cannot be divided by just 1 and 21,243, it is not a prime number.