What is fleventy five?

T.J Miller says he improvised it in this clip @ 2:50

https://www.youtube.com/watch?v=L_7ejTiGyb0

I think the fact that it doesn't work is even funnier. Clearly Erlich is bluffing and banking on the fact that no one would call him out and check the answer. Fleventy five sounds so believable, you can't help saying to yourself "Oh ok, that's what they must call it".

I cross posted this, and they said in Stack Overflow that this was just a throwaway joke in the show, which I guess I took too seriously.