Q: Is 671,780 a Prime Number?
A: No, 671,780 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 671780 can be evenly divided by 1 2 4 5 10 20 33,589 67,178 134,356 167,945 335,890 and 671,780, with no remainder.
Since 671,780 cannot be divided by just 1 and 671,780, it is not a prime number.