Q: Is 21,178 a Prime Number?
A: No, 21,178 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 21178 can be evenly divided by 1 2 10,589 and 21,178, with no remainder.
Since 21,178 cannot be divided by just 1 and 21,178, it is not a prime number.