A, B, C, D, E and F live on six different floors of the same building. The lowermost floor in the building is numbered 1, the floor above it, number 2 and so on till the topmost floor is numbered 6. F lives on a floor which is a prime number. The product of floors on which A and E live is 4. Only 2 people live above B. D lives immediately below C. How many people live between D and F?