Q: Is 1,628,721 a Prime Number?
A: No, 1,628,721 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 1628721 can be evenly divided by 1 3 9 27 179 337 537 1,011 1,611 3,033 4,833 9,099 60,323 180,969 542,907 and 1,628,721, with no remainder.
Since 1,628,721 cannot be divided by just 1 and 1,628,721, it is not a prime number.