the major that allows you to complete the regular pre-pharmacy prereq (e.g. Gen Bio, Gen Chem, Org Chem, Physics, Calculus/Stat, Human Ana+Phys, Microbio, etc) the quickest is Biology major.
As for how long, generally you can complete the regular pre-pharm prereq in ~ 2 years. If you wanna get your Bachelor, you can apply to pharmacy schools at the start of the Fall semester of your senior year.