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.
Even if he were a natural born citizen, he'd have to live in the US for 14 years first to be eligible.
We could us the Republican style of argument that "years" had a different meaning in the founding father's era as people died a lot sooner. Therefore "a year" was only the length of what we call "a day" now.