Since 2016, France is mainly divided into 18 administrative regions: 13 regions in metropolitan France (including the territorial collectivity of Corsica), and five located overseas. The regions are further subdivided into 101 departments, which are numbered mainly alphabetically. This number is used in postal codes and was formerly used on vehicle number plates. Among the 101 departments of France, five (French Guiana, Guadeloupe, Martinique, Mayotte, and Réunion) are in overseas regions (ROMs) that are also simultaneously overseas departments (DOMs), enjoy exactly the same status as metropolitan departments and are an integral part of the European Union.