Q: Is 642,728 a Prime Number?
A: No, 642,728 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 642728 can be evenly divided by 1 2 4 8 80,341 160,682 321,364 and 642,728, with no remainder.
Since 642,728 cannot be divided by just 1 and 642,728, it is not a prime number.