Q: Is 1,521,664 a Prime Number?
A: No, 1,521,664 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 1521664 can be evenly divided by 1 2 4 8 16 32 64 128 256 512 743 1,024 1,486 2,048 2,972 5,944 11,888 23,776 47,552 95,104 190,208 380,416 760,832 and 1,521,664, with no remainder.
Since 1,521,664 cannot be divided by just 1 and 1,521,664, it is not a prime number.