Alaska is a state in the United States, situated in the northwest extremity of the North American continent, with the international boundary with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait. Alaska is the largest state in the United States by area, the 4th least populous and the least densely populated of the 50 United States. Approximately half of Alaska's 731,449 residents live within the Anchorage metropolitan area. Alaska's economy is dominated by the oil, natural gas, and fishing industries, it has these resources in abundance. Alaska was purchased from Russia on March 30, 1867, for $7.2 million ($118 million adjusted for inflation) at approximately two cents per acre ($4.74/km²). The land went through several administrative changes before becoming an organized (or incorporated) territory on May 11, 1912, and the 49th state of the U.S. on January 3, 1959. Alaska is the largest state in the United States in land area at 586,412 square miles (1,518,800 km2), over twice the size of Texas, the next largest state. Alaska is larger than all but 18 sovereign countries. Counting territorial waters, Alaska is larger than the combined area of the next three largest states: Texas, California, and Montana. It is also larger than the combined area of the 22 smallest U.S. states.