The most men I've ever had at one time in a gangbang is probably about 25.
That is 25 different cocks, as far as penetrations go in one session, with guys coming back for more, sometimes more than once, and guys who blow and don't recover, that probably still adds up to at least 50 fucks and if you consider a cock in the mouth as a penetration, then you can double that.
I've run trains of up to 25 too as in our post "blow and go" but a gangbang gets more repeat fucks.