Reunion, Martinique, Guadeloupe and Guyana have the same status are other French department.
The others are territories.
Thanks to all these islands, France has the second largest Exclusive Economical Zone, just behind the USA.
Also, France is the 3rd country in the world when ranking the number of countries it shares a border with, after Russia and China (1st ex-equo)
Funny for a relatively small country