63645 -- U.S. ZIP code Municipality (1990): MILLCREEK, Missouri All ZIPs for this municipality (1990): 63645 Population (2000): 10713 Housing Units (2000): 5062 Land area (2000): 383.220805 sq. miles (992.537286 sq. km) Water area (2000): 0.801812 sq. miles (2.076684 sq. km) Total area (2000): 384.022617 sq. miles (994.613970 sq. km) Located within: Missouri (MO) Location: 37.548340 N, 90.305993 W