Q: Is 21,078 a Prime Number?
A: No, 21,078 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 21078 can be evenly divided by 1 2 3 6 9 18 1,171 2,342 3,513 7,026 10,539 and 21,078, with no remainder.
Since 21,078 cannot be divided by just 1 and 21,078, it is not a prime number.