Q: Is 243,503 a Prime Number?
A: No, 243,503 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 243503 can be evenly divided by 1 13 18,731 and 243,503, with no remainder.
Since 243,503 cannot be divided by just 1 and 243,503, it is not a prime number.