The Saturn V did not get it's name from the 5 F-1 engines on the S1 Stage. It got it's name because it was the fifth Saturn rocket proposed in the Saturn C family.
They proposed ideas for Saturn A-1,A-2,B-1,C-1,C-2,C-3,C-4, and C-5. The only ones that were developed were the C-1, which would become the Saturn I and Saturn IB, and the C5, which developed into the Saturn V vehicle.
They proposed ideas for Saturn A-1,A-2,B-1,C-1,C-2,C-3,C-4, and C-5. The only ones that were developed were the C-1, which would become the Saturn I and Saturn IB, and the C5, which developed into the Saturn V vehicle.