Europe is the world's second-smallest continent in terms of area, covering about 10,180,000 square kilometres (3,930,000 sq mi) or 2.0% of the Earth's surface. The only continent smaller than Europe is Australia. In terms of population, it is the third-largest continent (after Asia and Africa) with a population of 710,000,000 or about 11% of the world's population. However, the term continent can refer to a cultural and political distinction or a physiographic one, leading to various perspectives about Europe's precise borders, area, and population. Russia is the largest country by area and population in the European continent. Europe is the birthplace of the European Union, a union of twenty-seven independent states based on the European Communities and founded to enhance political, economic and social co-operation and integration.