Afghanistan is 3,846 times larger than Sioux Falls, South Dakota.
Area: 652,230 km2 World Factbook
Population: 31,822,848 (July 2014) World Factbook
Afghanistan, officially the Islamic Republic of Afghanistan, is a landlocked country located in Central Asia and South Asia. It has a population of around 31 million people making it the 42nd most populous country. Wikipedia
Area: 170 km2 calculated
Sioux Falls is the largest city in the U.S. state of South Dakota. It is the county seat of Minnehaha County, and also extends into Lincoln County to the south. Wikipedia