Q: Is 1,638,641 a Prime Number?
A: Yes, 1,638,641 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 1638641 can be evenly divided by 1 and 1,638,641, with no remainder.
Since 1,638,641 can be divided by just 1 and 1,638,641, it is a prime number.