Q: Is 20 a Prime Number?
A: No, 20 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 20 can be evenly divided by 1 2 4 5 10 and 20, with no remainder.
Since 20 cannot be divided by just 1 and 20, it is not a prime number.