Overnight in airport

I have a 13 hour layover from 11pm until noon the following day, I would like to leave the airport and briefly see the city in this time frame, as well as get a hotel for the night. Would this be possible without chancing missing my flight? Would I be able to see anything of significance in this time frame? Also, am I better off getting a room at the airport or off site? I will be coming from Cambodia and leaving to the US if that makes a difference. Thank you!