[ajarmst]

A reasonable case can be made that (if we employ the "is evenly divisible by 2/has 2 as a factor" definition) zero is not composite, so has no factors and therefore can't be even. I happen to disagree, but it's not clearly right or wrong. This is why when mathematicians from different subdisciplines/communities spend a fair bit of time on "when you use the term ... what do you mean?" Outside a shared definition of exactly what "even" means, the question is meaningless, and within one, it's trivial---the least interesting possible questions in mathematics, but we seem to spend a lot of time on them.