Q: Is 721,143 a Prime Number?
A: No, 721,143 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 721143 can be evenly divided by 1 3 9 27 29 81 87 261 307 783 921 2,349 2,763 8,289 8,903 24,867 26,709 80,127 240,381 and 721,143, with no remainder.
Since 721,143 cannot be divided by just 1 and 721,143, it is not a prime number.