Simon Cowell is just like a ''nine-year-old'' boy as he likes to play with toys and go roller skating.

The music mogul is a big kid who loves to spend his spare time watching cartoons and dashing down the road on his roller skates, according to 'Britain's Got Talent' co-hosts Ant and Dec.

Simon - who is head judge on the TV talent show - has had plenty of practice on wheels after spending a lot of his time at roller discos in London's Battersea area when he was younger,

Speaking at the 'Britain's Got Talent' auditions at the London Palladium on Sunday (20.01.13), the duo told BANG Showbiz: ''We know he is a fan of robots and cartoons. Just think of what a nine year old boy would like and that's kind of what he likes. Cars, robots and cartoons, oh and roller skating - he loves roller skating. He used to go to the roller boogie in Battersea in the 1970s.''

Although Simon will turn 54 later this year, the presenting duo has a mind like a youngster because is imagination often runs away with him.

They added: ''He said one of my favourite quotes ever the other day. There was this singer auditioning with a really deep voice, a baritone singer, and Simon went, 'That is how I imagine a giant would sound if a giant was singing.'

''You just think, 'Where is your mind to come out with something like that? Why are you thinking about giants singing? You're in your 50s, man!' He's gone la la, well he's always been like that.''