^^Well, since Riker loves poker, I'm sure there are plenty of decks on board.
I checked the series bible and couldn't find any reference to the number of decks. But apparently it's 80.7 meters tall, including the sensor pod. The refit Enterprise
was 71.3 meters tall, and it had 21 decks, plus a little extra for the tops of the nacelles. So maybe something in the vicinity of 24-25 decks, give or take, if you count the sensor pod and its connectors?