How many people lived in the aztec cptial when it was at its highest of it cultrue

The population in 1519 was estimated to be about 400,000 people, the largest residential concentration in Mesoamerican history. It contained the palace of Montezuma II, said to consist of 300 rooms, as well as hundreds of temples. It was destroyed by the Spanish conquistadores under Hernán Cortés in 1521.