Q: Is 642,623 a Prime Number?
A: Yes, 642,623 is a prime number.
A prime number is a natural number, greater than one, that can only be divided by 1 and itself.
The number 642623 can be evenly divided by 1 and 642,623, with no remainder.
Since 642,623 can be divided by just 1 and 642,623, it is a prime number.