Ad infinitum

Mordechai's friend introduced him to the number 'googol'. He was fascinated by the enormity of this number (which I'm sure he can't even fathom because I sure as heck can't!). A snippet from today's conversation:

Mordechai: What number comes after a googol?

Me: A googol and one.

Mordechai: No. I mean, like, after a googol and ninety-nine.