Justin Timberlake finds changing his son Silas' diapers an "extremely humbling experience".

In a new interview, the singer told Carson Daly that he looks at everything differently now, ever since his wife Jessica Biel gave birth to their first child 13 months ago (Apr15).

"Yes, having a little man in the house now changes everything!" Justin laughed. "When I used to clean up my dog's poop, it was like it was a science project; I wouldn't get very close to it. When you have a kid and there's poop, you got to get in there!

"Nothing trumps your kid's butt cleanliness, so you just have to get in there! Here's what I'll say - all I know is I don't know what the hell I did before. It's an extremely humbling experience, and I've never had more poop on my person!" joked the star, who released his first single in three years, Can't Stop The Feeling, on Friday (06May16).

The song is due to feature in the forthcoming Dreamworks movie Trolls, which is due out in November (16) and features the voices of Anna Kendrick, Zooey Deschanel and the singer himself.

The 35-year-old admitted that Silas partly inspired him to take on a role in the movie, as Justin thought by the time of the film's release, his boy would want to have all the Trolls toys.

"I think it was serendipitous in that way where having just had a son and going like, 'Wow! This is kind of cool!' But who knows? By the time he watches the movie, he'll probably be like, 'Dad! That's not cool!'" he quipped.

Despite family life keeping him busy, Justin has revealed he's working on his fifth studio album, but warned his die-hard fans that his new sound may be different to what they were expecting.

"Growing up in Tennessee - very central of the country - Memphis is known as being the birthplace of rock and roll, but also the home of the blues, but Nashville's right down the street so there's a lot of country music," he explained.