7. United States Of America: –
United States of America is richest in terms of holding the financial control over the economy of entire world. It is at number 7 in terms of richest countries in the world. Its GDP is 49,965.27 USD and has a population of 313.9 million as per 2012 survey. The capital of United States of America is Washington D.C. and is the center of attraction for people from entire world.