iPhone 3gs not turning on but on?

[loganjb25]

Hi guys, I have a iPhone 3gs 16gb black. It got a crack in screen but I dont think its big enough to cut the screen out but the main thing is the iPhone wont turn on, so i think. It gets hot on the back like a normal running iPhone, when i push the silent button no vibration. When i plug into itunes though it still does not come up. It does charge how ever i believe. but not 100% sure. Can anyhelp? Thanks, also when on the logic something black with the apple logo on it and some number gets extremely hot, well hot, thats why i think its running