Hannibal, MO -- U.S. city in Missouri Population (2000): 17757 Housing Units (2000): 7886 Land area (2000): 14.610726 sq. miles (37.841604 sq. km) Water area (2000): 0.471622 sq. miles (1.221496 sq. km) Total area (2000): 15.082348 sq. miles (39.063100 sq. km) FIPS code: 30214 Located within: Missouri (MO), FIPS 29 Location: 39.704065 N, 91.377378 W ZIP Codes (1990): 63401 Note: some ZIP codes may be omitted esp. for suburbs. Headwords: Hannibal, MO Hannibal