During an interview with former aide David Axelrod, in which President Barack Obama said that if he were able to run again for president, he could have won the 2016 election, the outgoing president revealed the first thing he's going to do when his second term officially ends: write a book and do some soul-searching.

"I'm gonna start thinking about the first book ... I want to write. We've got to unpack, and ... I have to be quiet for a while," he said.

Obama explained that he didn't mean he plans to be politically quiet, but rather to reflect on all areas of his life.

"I don't mean politically. I mean internally. I have to still myself," he said. "You have to get back in tune with your center and process what happened before you make a bunch of good decisions."

Donald Trump's predecessor went on to say that his long-term goal is to not be "the guy ... who's just hanging around re-living old glories."

On a scenario in which he would have been able to run against Trump, Obama said: "I am confident in this vision because I'm confident that if I had run again and articulated it, I think I could've mobilized a majority of the American people to rally behind it.

"I know that in conversations that I've had with people around the country -- even some people who disagreed with me -- they would say, 'The vision, the direction that you point towards is the right one.'"

Read the full transcript of Obama's interview with Axelrod on CNN.