Sudan, officially the Republic of the Sudan, is a country in Northeast Africa. It borders the Central African Republic to the southwest, Chad to the west, Libya to the northwest, Egypt to the north, the Red Sea to the east, Eritrea and Ethiopia to the southeast, and South Sudan to the south. Sudan has a population of 50 million people as of 2024 and occupies 1,886,068 square kilometres (728,215 square miles), making it Africa's third-largest country by area and the third-largest by area in the Arab League. It was the largest country by area in Africa and the Arab League until the secession of South Sudan in 2011; since then both titles have been held by Algeria. Sudan's capital and most populous city is Khartoum.