Katy Perry & Russell Brand Divorce -- No Prenup, No Regrets

Katy Perry and Russell Brand never entertained the idea of signing a prenup -- and if they could do it all over again ... they wouldn't have changed a thing, sources close to the couple tell TMZ.

According to sources, Katy and Russell's marriage happened so fast, they never really had the opportunity to summon their lawyers and hash out a prenup ... nor did either really believe they needed one.

We’re told both felt comfortable one wouldn’t screw the other in the event of a divorce -- they both knew where the other person stood on money, life, religion ... everything.

TMZ broke the story ... Russell refused to accept $20 million of Katy's money he was entitled to as part of the divorce -- exactly half the money she made during the course of their marriage.

Sources tell us, Russell was never a materialistic person and never spent much -- he never got into entertainment for the money.

As one source put it, "Russell is a very simple person who doesn’t need much to make him happy."

The source adds, “He would never take money that [Katy] earned. That’s not Russell. And if it was the other way around, Katy wouldn’t have taken it either. They respect each other too much."