The Republic of South Africa is a sovereign state in southern Africa and a member of the United Nations. It is the southernmost country in Africa, with nine provinces bounded by 2,798 km of coastline along the South Atlantic and Indian Oceans to the south, Namibia, Botswana, and Zimbabwe to the north, Mozambique and Eswatini to the east and northeast, and enclosing Lesotho. It covers 1,221,037 square kilometres and has a population of over 63 million. Pretoria is the administrative capital, Cape Town is the legislative capital (seat of Parliament), and Bloemfontein is the judicial capital. Johannesburg is the largest and most populous city, followed by Cape Town and Durban. The executive branch follows the Westminster system, divided into cabinet and civil service, with public administration managed by national departments headed by director-generals.