Q: Is 243,991 a Prime Number?
A: No, 243,991 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 243991 can be evenly divided by 1 11 41 451 541 5,951 22,181 and 243,991, with no remainder.
Since 243,991 cannot be divided by just 1 and 243,991, it is not a prime number.