Q: Is 642,820 a Prime Number?
A: No, 642,820 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 642820 can be evenly divided by 1 2 4 5 10 20 32,141 64,282 128,564 160,705 321,410 and 642,820, with no remainder.
Since 642,820 cannot be divided by just 1 and 642,820, it is not a prime number.