Brazil.

Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is also the world's fifth-largest country by area and the seventh-largest by population, with over 213 million people. Brazil is a federation composed of 26 states and a Federal District, which hosts the capital, Brasília. Its most populous city is São Paulo, followed by Rio de Janeiro. Brazil has the most Portuguese speakers in the world and is the only country in the Americas where Portuguese is an official language.