Q: Is 1,641,666 a Prime Number?
A: No, 1,641,666 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 1641666 can be evenly divided by 1 2 3 6 13 26 39 78 169 338 507 1,014 1,619 3,238 4,857 9,714 21,047 42,094 63,141 126,282 273,611 547,222 820,833 and 1,641,666, with no remainder.
Since 1,641,666 cannot be divided by just 1 and 1,641,666, it is not a prime number.