Aryabhata pronunciation (IAST: Āryabhaṭa, Sanskrit: आर्यभट) or Aryabhata I (476–550 CE) was the first in the line of great mathematician-astronomers from the classical age of Indian mathematics and Indian astronomy. His most famous works are the Āryabhaṭīya (499 CE, when he was 23 years old) and the Arya-siddhanta.
The works of Aryabhata dealt with mainly mathematics and astronomy. He also worked on the approximation for pi.