Prather also provided five rebounds and five assists for the Gators (2-1), who broke open a close game with a 12-6 run opening the second half.
Dorian Finney-Smith added 17 points and nine boards off the bench.
Kasey Hill helped out with 14 points, six assists and five steals for Florida.
The Trojans (0-2) were paced by Will Neighbour with 21 points.
James White contributed 16 points and nine rebounds.