The stinky kidz

How do I improve my son 13, hygiene. He is incredibly hard to get into the shower. And when he does their is very little water pressure, and he smells just as bad as before he got in one. He rarly puts on deodorant, only when we harp him about it. He will wear the same shirt forever if we let him. And im lucky to wash one pair of his underwear a week.
It seems to be the norm among the teens around here. All smelly. How do we address this. He gets annoyed when we bring it up.. he stinks. His room stinks, and he leave his stinks where ever he goes.