As a point of fact, the Broncos have 13 on the current roster.
We know three are locks to make the team — Courtland Sutton, Jerry Jeudy and KJ Hamler. That leaves, at most, three more receiver spots on offense. Perhaps there are two on special teams, though one seems more likely — either as a gunner or returner. Then two or three more could end up on the practice squad.
Put the three locks aside, and let’s say Denver only keeps one for special teams and two on the practice squad, that’s six spots and 10 players.