Bangladesh, officially the People's Republic of Bangladesh, is a country in South Asia. It is the eighth-most populous country in the world, with a population exceeding 161 million people. In terms of land mass, Bangladesh ranks 92nd, spanning 147,570 square kilometres (56,980 sq mi), making it one of the most densely-populated countries in the world. Bangladesh shares land borders with India to the west, north, and east, Myanmar to the southeast, and the Bay of Bengal to the south. Dhaka, the capital and largest city, is the nation's economic, political and cultural hub. Chittagong, the largest sea port, is the second largest city. With numerous criss-crossing rivers and inland waterways, the dominant geographic feature of Bangladesh is the Ganges delta. Speakers of the official Bengali language, who form the Bengali ethnic group, make up 98% of the population. Its large Muslim population makes Bangladesh the fourth-largest Muslim-majority country in the world. The constitution declares Bangladesh a secular, Muslim-majority country.