Bangladesh, officially the People's Republic of Bangladesh, is a country in South Asia. It is the eighth-most populous country in the world and seventh most densely populated with a population of 173,562,364 in an area of 148,460 square kilometres (57,320 sq mi). Bangladesh shares land borders with India to the north, west, and east, and Myanmar to the southeast. To the south, it has a coastline along the Bay of Bengal. To the north, it is separated from Bhutan and Nepal by the Siliguri Corridor, and from China by the mountainous Indian state of Sikkim. Dhaka, the capital and largest city, is the nation's political, financial, and cultural centre. Chittagong is the second-largest city and the busiest port. The official language is Bengali, with Bangladeshi English also used in government.