Simon Cowell thinks his quirky habits are a sign of madness.

The music mogul has a fear of the number 13, and can't bring himself to walk up a flight of stairs if there are 13 steps.

While 54-year-old Simon is busy awaiting the arrival of his first child with his girlfriend Lauren Silverman, he'll no doubt be hoping the baby isn't born on the 13th.

"I have some quirky habits. Everything about me is about numbers so for some reason I am always counting numbers in the head. Even if I walk up the stairs I am counting how many steps and if it is 13 I make sure it is not going to be 13.

"So the last number cannot be 13. It can't be 67 either because 6 and 7 adds up to 13. So I will walk an extra step. It is a kind of sign of madness actually," he explained to the British newspaper Daily Star.

Simon isn't the only one to suffer this fear though and the medical name for it is triskaidekaphobia.

Aside from worrying about the unlucky digits Simon is getting into dad mode, but friends have revealed it's unlikely he will wed Lauren.

The infamous bachelor started dating Lauren when she was still married to Simon's former pal Andrew Silverman, with who she has son Adam.

"Simon and Lauren have no plans to marry. They are concentrating on the safe arrival of their unborn child for the foreseeable future," an insider told British newspaper The Mirror.

"Lauren is due to spend lots of quality time with her son Adam in the next few weeks - as she prepares for the birth of her and Simon's child. And Simon is totally focused on becoming a father for the first time."

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