[bluepnume]

It's hardly odd.

"Even" just means "divisible by 2"

"2 is the only prime that is divisible by 2" "3 is the only prime that is divisible by 3" "5 is the only prime that is divisible by 5"

...

"N is the only prime that is divisible by N"

[thehappypm]

Exactly, we could also have a word for multiple of three or multiple of five

[evanb]

Threeven is used semi-seriously.

[latexr]

Your explanation is true of every prime. I’m pretty sure GP just meant that “2 is the only prime with the additional characteristic of being an even number”. So it’s odd (read “interesting”) in that sense, like if it would be if (for example) any number were to be the sole prime composed of exactly X digits.