The word philosophy was probably coined by Pythagoras.  
his theorem is very good
Pythagoras's theorum has more to do with math than philosophy.  
true, but everything is related
Yes,. Pythagoreanism is highly invluential in both mathmatics and philosophy. 
any other subjects he is known for?
Pythagoras
Pythagoras of Samos () was an ancient Ionian Greek philosopher and the eponymous founder of Pythagoreanism. His political and religious teachings were well known in Magna Graecia and influenced the philosophies of Plato, Aristotle, and, through them, Western philosophy. Knowledge of his life is clouded by legend, but he appears to have been the son of Mnesarchus, a gem-engraver on the island of Samos. Modern scholars disagree regarding Pythagoras's education and influences, but they do agree that, around 530 BC, he travelled
tetractys was "so admirable, and so divinised by those who understood [it]," that Pythagoras's students would swear oaths by it. Andrew Gregory concludes that the tradition linking Pythagoras to the tetractys is probably genuine.
Modern scholars debate whether these numerological teachings were developed by Pythagoras himself or by the later Pythagorean philosopher Philolaus of Croton. In his landmark study "Lore and Science in Ancient Pythagoreanism", Walter Burkert argues that Pythagoras was a charismatic political and religious teacher, but that the number philosophy attributed to him