Aragorn lived to be much older than the "regular men" in middle earth, because he was a descendant of the High Men, who had some Elvish blood in their line.

He was actually a servant to the beings sent to watch over Middle Earth by God (or the being who passes for God in Tolkein's Lore)…so he was sort of a servant of the demi-Gods. Sauron was also one of these beings. I think he was a Maiar, who were the servants to the Valar.