Q: Is 840 a Prime Number?
A: No, 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 840 can be evenly divided by 1 2 3 4 5 6 7 8 10 12 14 15 20 21 24 28 30 35 40 42 56 60 70 84 105 120 140 168 210 280 420 and 840, with no remainder.
Since 840 cannot be divided by just 1 and 840, it is not a prime number.