2 is the "oddest prime of all." Regarding the old humorous "math joke" that 2 is the only even prime, thus it is the "oddest" prime of all. I have a bone to pick with this. I don't think the idea of "even" numbers is any more special than numbers that are divisible by 3 or 5, or anything else. Divisibility by 2 just has a special name. So we say that 2 is an 'odd' prime because it is the only prime that is even. But, if we equivalently say that 2 is the only prime that is divisible by 2, we find that there is nothing special about this at all, because any prime p has the property that it is the only prime divisible by p by definition. Thus, there is nothing odd about the prime number 2. End rant.