No Person except a natural born Citizen, or a Citizen of the United States, at the time of the Adoption of this Constitution, shall be eligible to the Office of President; neither shall any Person be eligible to that Office who shall not have attained to the Age of thirty-five Years, and been fourteen Years a Resident within the United States.

The text of the restriction of who can be President allowed for any citizen at the time of the adoption of the Constitution to be president as well.

There is no one left alive who meets that requirement, of course.