Paris HiltonParis Hilton may be a fan of shopping.

But don't count on the socialite to count up her post-spree receipts.

The party princess has inadvertently revealed that she doesn't have a head for figures.

It's a shocker, we know, but it transpires Paris isn't on intimate terms with all things bills and utilities.

The bombshell revealed itself during a Miami court case Ms Hilton is currently involved in, when attorneys quizzed the star about who deals with her finances.

"I don't know. I'm assuming, like, whoever pays my bills. I never ask about that stuff," the anti-airhead replied.

"I've never seen a phone bill of mine in my life," she added.

However, there could be good reason for this, since Paris' lawyer Michael Weinstein went onto testify that his client is "the single busiest person on the planet".

We're assuming "busy" relates to her social calendar; we somehow doubt Paris is slogging her butt off on the factory floor...

During the ongoing case, in which Paris is defending herself against a claim that she didn't do enough to promote the 2006 flop movie Pledge This, court documents have revealed that the 28-year-old earned $15 million (£9.9 million) in 2006 and 2007 from promotions.

Nice work, if you can get it.