Yes. 33 = 3 * 11. You can tell it's divisible by 3 because adding the digits together gives six, which is divisible by 3.
A composite
61
Yes.
It is a composite number.
5x3x29
Prime
85 is composite.
1 is a prime number.
21 is a composite number.
21 is a composite number.
63 is a Composite Number.
180 is a Composite Number.