Q: Is 641,421 a Prime Number?
A: No, 641,421 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 641421 can be evenly divided by 1 3 9 11 19 31 33 57 93 99 121 171 209 279 341 363 589 627 1,023 1,089 1,767 1,881 2,299 3,069 3,751 5,301 6,479 6,897 11,253 19,437 20,691 33,759 58,311 71,269 213,807 and 641,421, with no remainder.
Since 641,421 cannot be divided by just 1 and 641,421, it is not a prime number.