Atlanta ( /ətˈlæntə/, stressed /ætˈlæntə/, locally  /ætˈlænə/) is the capital and the most populous city in the U.S. state of Georgia with a 2010 population of 420,003. Atlanta is the cultural and economic center of the Atlanta metropolitan area, which is home to 5,268,860 people and is the ninth largest in the U.S. It is a major component of a growing southeastern megalopolis known as the Piedmont Atlantic Megaregion. Atlanta is the county seat of Fulton County, and a small portion of the city extends eastward into DeKalb County.