With an area of 1964375 square kilometers, it is the fifth largest country in America and the fourteenth largest country in the world. Population 1. With a population of 2.3 billion (20 17), it is the most populous country in the world, the largest Spanish-speaking country in the world and the second largest country in Latin America. Mexico is a federal country, including 32 states; Mexico City, its capital and largest city, is also a state.