Q: Is 81,920 a Prime Number?
A: No, 81,920 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 81920 can be evenly divided by 1 2 4 5 8 10 16 20 32 40 64 80 128 160 256 320 512 640 1,024 1,280 2,048 2,560 4,096 5,120 8,192 10,240 16,384 20,480 40,960 and 81,920, with no remainder.
Since 81,920 cannot be divided by just 1 and 81,920, it is not a prime number.