Russia is the world's largest country, with a total area of 17, 098, 242 square kilometers. It was formerly known as the Union of Soviet Socialist Republics (USSR), which was a single-party Marxist–Leninist state that existed from 1922 to 1991. Russia is the most populous country in Europe and the ninth most populous country in the world, with a population of over 144 million people. It is also the world's largest country by landmass, spanning 11 time zones and two continents.