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The United States has an area of 9,826,675 square kilometers (3,794,101 square miles), while Mexico has 1,972,550 square kilometers (761,606 square miles). Almost five countries the size of Mexico would fit inside the United States.
From the north west island of Rondo to the Papua New Guinean border on the south east is about 5300 km or 3550 miles. It is comparable with the distance from Juneau, Alaska to Miami, Florida.
Russia is the largest country at over 17,000,000 km2. The US is the third largest at about 9,500,000 km2. Russia is about 1.75 times the size of the US.