Q: Is 1,661,503 a Prime Number?
A: Yes, 1,661,503 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 1661503 can be evenly divided by 1 and 1,661,503, with no remainder.
Since 1,661,503 can be divided by just 1 and 1,661,503, it is a prime number.