What was the population in India before the European arrival in 1492?

Of India? Europeans had been there before, but arrived by sea in 1498 when the subcontinent had probably rather over 100 million inhabitants. But it wasn't a united country at that time.

Europeans arrived in 1492 in the Americas, often called the Indies in the next century. Nobody knows what the population there was because so many later died of disease before proper counts: estimates have ranged from 8.4m (too low) to 112m (too high).