Yes.
even divisor 4
That depends what numbers. If you mean ALL even and odd numbers, the only common factor or divisor is 1.
The GCF is 2.
Never.
No.
No.
No. Odd numbers only have odd factors. They could not have an even factor in common.
No, always odd.
It is an odd number, so it has no even factors.
No, always odd.
No. The GCF of 6 and 15 is 3.
There is no greatest common multiple as whatever number is claimed to be the greatest, the lowest common multiple of them (216) can be added to get an even greater common multiple.