This was covered very well by u/missingpuzzle in December 2013 here:

https://www.reddit.com/r/AskHistorians/comments/1tqfef/what_is_the_oldest_recorded_human_name/

Hi there -- this question has been asked here a few times before, so some of these past threads may be of interest. (Spoiler alert: it's probably an Egyptian pharaoh named Iry-Hor.)

https://www.reddit.com/r/AskHistorians/comments/1tqfef/what_is_the_oldest_recorded_human_name/

https://www.reddit.com/r/AskHistorians/comments/21jjpq/who_is_the_oldest_person_known_to_mankind/

https://www.reddit.com/r/AskHistorians/comments/q8726/oldest_person_we_know_to_have_existed/

https://www.reddit.com/r/AskHistorians/comments/3v355s/who_is_the_oldest_named_human_for_whom_we_have/

u/namirual covered the Gilgamesh question comprehensively here:

https://www.reddit.com/r/AskHistorians/comments/4mie5y/what_makes_the_difference_between_a_figure_being/d3vzt47/