Q: Is 638,423 a Prime Number?
A: Yes, 638,423 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 638423 can be evenly divided by 1 and 638,423, with no remainder.
Since 638,423 can be divided by just 1 and 638,423, it is a prime number.