The population, which accounts for world's 17.5 per cent population, comprises 623.7 million males and 586.5 million females, said a provisional 2011 Census report. China is the most populous nation acounting for 19.4 per cent of the global population.
The country's headcount is almost equal to the combined population of the United States, Indonesia, Brazil, Pakistan, Bangladesh and Japan put together, it said.
The population has increased by more than 181 million during the decade 2001-2011, the report said. The growth rate in 2011 is 17.64 per cent in comparison to 21.15 per cent in 2001.
The 2001-2011 period is the first decade -- with exception of 1911-1921 -- which has actually added lesser population compared to the previous decade, Registrar General of India and Census Commissioner of India C Chandramauli said in presence of Home Secretary Gopal K Pillai.
Among the states and Union territories, Uttar Pradesh is the most populous state with 199 million people and Lakshadweep the least populated at 64,429.
The combined population of UP and Maharashtra is bigger than that of the US.
The highest population density is in Delhi's north-east district (37,346 per sq km) while the lowest is in Dibang Valley in Arunachal Pradesh (just one per sq km).
The Census indicated a continuing preference for male children over female children. The latest child sex ratio in is 914 female against 1,000 male-the lowest since Independence.
Source : ET