The Northern Mariana Islands, officially the Commonwealth of the Northern Mariana Islands, is one of five inhabited American insular areas. It is one of two territories with US "commonwealth" status; the other is Puerto Rico. It consists of fifteen islands in the northwestern Pacific Ocean. The CNMI and Guam together comprise the Marianas archipelago. The United States Department of the Interior cites a landmass of 183.5 square miles (475.26 km2). According to the 2010 United States Census, 53,883 people were living in the CNMI at that time. The vast majority of the population resides on Saipan, Tinian, and Rota.