The United States of America (USA) is a sovereign country in North America. It is commonly called the United States (U.S. or US) or America. There are forty-eight states that border each other and Washington, D.C., the capital district. These states are between the Pacific and Atlantic Oceans. They are bordered by Canada to the north and Mexico to the south. The state of Alaska is in the northwest of the continent, with Canada to its east and Russia to the west across the Bering Strait. The state of Hawaii is an archipelago in the mid-Pacific. The country also possesses some territories, or insular areas, in the Caribbean and Pacific. The city with the highest population is New York City. At 3.79 million square miles (9.83 million km) and with about 331 million people, the United States is the third or fourth-largest country by total area and the third-largest by land area and by population.