How old is Donald Trump?

In addition to Donald Trump arguably being one of the most controversial presidents in U.S. history, he is also the oldest occupier of the Oval Office.

When President Trump was sworn in on Jan. 20, 2017, he was 70 years, seven months and seven days old.

He broke a record held by Ronald Reagan since his inauguration exactly 36 years before. Reagan was just shy of turning 70 when he took office in 1981 at 69 years, 11 months and 11 days old.

Rounding out the top five oldest presidents are:

• William Henry Harrison, who took office 24 days after his 68th birthday in 1841 — and died just 31 days later of pneumonia, serving the shortest presidential term ever.

• James Buchanan, the only commander in chief from Pennsylvania, was 65 years, 10 months and 10 days old when he was sworn in 1857.

• George H.W. Bush, who had been Reagan’s vice president and the father of a future president, was 64 years, 6 months and 28 days old when he began his first — and only — presidential term in 1989.

While slightly more than half of the country’s leaders were in their 50s when their terms began, there were a handful in their 40s, so who takes the prize for being the youngest?

Teddy Roosevelt, who was 42 years, 10 months and 19 days old when he took office in 1901.

He’s followed by:

• John F. Kennedy, who was 43 years, seven months and 23 days old when he was inaugurated in 1961.

• Bill Clinton, who took oath in 1993 at 46 years, five months and seven days old.

• Ulysses S. Grant comes next, having been 46 years, 10 months and 11 days old when took office in 1869.

• Trump’s predecessor Barack Obama, who was 47 years, five months and 17 days old at his first inauguration in 2009 rounds out that top five.