Q: Is 621,423 a Prime Number?
A: No, 621,423 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 621423 can be evenly divided by 1 3 9 11 33 99 6,277 18,831 56,493 69,047 207,141 and 621,423, with no remainder.
Since 621,423 cannot be divided by just 1 and 621,423, it is not a prime number.