Q: Is 521,420 a Prime Number?
A: No, 521,420 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 521420 can be evenly divided by 1 2 4 5 10 20 29 31 58 62 116 124 145 155 290 310 580 620 841 899 1,682 1,798 3,364 3,596 4,205 4,495 8,410 8,990 16,820 17,980 26,071 52,142 104,284 130,355 260,710 and 521,420, with no remainder.
Since 521,420 cannot be divided by just 1 and 521,420, it is not a prime number.