Brazil (Portuguese: Brasil [bɾaˈziw]), officially the Federative Republic of Brazil (Portuguese: República Federativa do Brasil, listen (help·info)), is the largest country in both South America and Latin America. At 8.5 million square kilometers (3.2 million square miles) and with over 208 million people, Brazil is the world's fifth-largest country by area and the sixth most populous. The capital is Brasília, and the most populated city is São Paulo. It is the largest country to have Portuguese as an official language and the only one in the Americas. Bounded by the Atlantic Ocean on the east, Brazil has a coastline of 7,491 kilometers (4,655 mi). It borders all other South American countries except Ecuador and Chile and covers 47.3% of the continent's land area. Its Amazon River basin includes a vast tropical forest, home to diverse wildlife, a variety of ecological systems, and extensive natural resources spanning numerous protected habitats. This unique environmental heritage makes Brazil one of 17 megadiverse countries, and is the subject of significant global interest and debate regarding deforestation and environmental protection.