Vietnam, officially the Socialist Republic of Vietnam (SRV), is a country at the eastern edge of mainland Southeast Asia, with an area of 331,212 square kilometres (127,882 sq mi) and a population of over 100 million, making it the world's fifteenth-most populous country. Vietnam shares land borders with China to the north, and Laos and Cambodia to the west. It shares maritime borders with Thailand through the Gulf of Thailand, and the Philippines, Indonesia, and Malaysia through the South China Sea. Its capital is Hanoi and its largest city is Ho Chi Minh City (commonly referred to by its former name, Saigon).