Q: Is 687,840 a Prime Number?
A: No, 687,840 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 687840 can be evenly divided by 1 2 3 4 5 6 8 10 12 15 16 20 24 30 32 40 48 60 80 96 120 160 240 480 1,433 2,866 4,299 5,732 7,165 8,598 11,464 14,330 17,196 21,495 22,928 28,660 34,392 42,990 45,856 57,320 68,784 85,980 114,640 137,568 171,960 229,280 343,920 and 687,840, with no remainder.
Since 687,840 cannot be divided by just 1 and 687,840, it is not a prime number.