Source Source wikipedia Source the nation’s youngest president a list of U.S. presidents Source third-youngest president U.S. Presidents' ages upon assuming office English wikipedia says: third-youngest president ever to be inaugurated, ever to be inaugurated, no one over 70 has become president Source oldest president longest-retired president in U.S. history English third-youngest president third-youngest president English The youngest living former president is Bill Clinton [List of Presidents] wikipedia Source third-youngest president the nation’s youngest president oldest president ever to be inaugurated, office Source Source English Source ever to be inaugurated, Source List of Presidents of the United States by age English Source longest-retired president in U.S. history ever to be inaugurated, ever to be inaugurated, youngest person to become president