EXCLUSIVE

Drake Bell -- a huge Nickelodeon child actor who starred in "Drake & Josh" -- has filed for bankruptcy ... TMZ has learned.

The 26-year-old actor just filed legal docs, claiming he's in the hole to the tune of $581,000.

As for the breakdown, Bell lists the value of his house at $1.575 million. The bad news -- he's underwater, owing $1.597 mil.

Bell says he's only pulling in $2,820 a month, but his expenses total a whopping $18,771.

The fattest year Bell lists is 2012, when he made $408,000, but the next year he made an anemic $14,099.