(CNN) Given the form he's been showing in the last 14 months, most people aren't surprised that Roger Federer is once again world No. 1.

Federer has enjoyed a remarkable 14 months -- winning three grand slams -- after returning to the sport following a lengthy layoff due to a knee injury.

But at the age of 36, and the oldest person to become world No. 1 in the sport, the reality is that the 20-time grand slam champion is closer to the end of his career than the beginning.

So how does someone whose life has been dominated by tennis feel about eventually having to retire?

"I got a little glimpse into it when I was out for six to eight months in 2016," Federer told CNN Sport's Don Riddell, referring to his rehabilitation from that knee injury, "and I actually enjoyed it a lot!"

Federer is dominating the men's game -- at the age of 36.

He says he was able to spend time at home with his family in Switzerland and focused more on his charity -- the Roger Federer Foundation -- which supports child education projects in Southern Africa.

"I'll never get bored, so I'm looking forward to it actually," added Federer.

"I have a great group of friends around me, in particularly my wife and parents are amazing so I always know I'll be fine once I retire and when I'm home."

'Great moments'

However, Federer's fans can breathe a sigh of relief: he's in no rush to call time on his tennis career.

READ: Roger Federer wins Australian Open and 20th major after beating Marin Cilic

"In a way I can't wait for it (retirement), but it should wait for the moment.

"Times are great at the moment as a tennis player. These are great moments."

Federer regained the world No. 1 spot for the first time since 2012 after beating Dutchman Robin Haase. He then went on to win the 2018 Rotterdam Open against Bulgaria's Grigor Dimitrov.

While most aren't surprised he's back at the top, Federer himself couldn't quite believe it.

"This one definitely comes very surprising to me because -- getting back to world No. 1, having had the surgery in 2016, and not knowing if I was ever going to win another grand slam," he said.

"So this is an incredible comeback for me, definitely my best one ever."

Switzerland's Roger Federer serves to Robin Haase of the Netherlands during their Rotterdam Open quarter-final.

Federer underwent knee surgery two years ago -- an injury not acquired by the intensity of his chosen sport, but while bathing his children.

He finally returned to the game last year after that lengthy rehabilitation.

Universally adored

Federer points to his upbringing as the reason he's been able to achieve such great success and popularity during his career.

"My background has been a good one. My parents have always kept me very grounded -- I come from a normal village, normal city, normal country ... I think it was a great way for me to grow up."

He also says he has a lot of respect for his fellow opponents: "I have become the player I am today because they have made me improve."

Switzerland's Roger Federer has become the oldest person to become world No. 1.

While it's nice to be popular, Federer says, he knows he can't win everyone over.

"I try to have a very strong character, to be honest and open. I know I can't please everyone. But I try to represent my sport in the best possible way."

For now, though, Federer's challenge for 2018 is to defend his titles, starting with Indian Wells in March and then Miami in April.