NEW YORK (Reuters) - When it comes to bestselling authors James Patterson is hard to beat. He has been called the busiest man in publishing and is the first author to achieve 10 million in ebook sales.

His thriller, "Mistress," soared to the top of the Publishers Weekly bestseller list shortly after its August release, where it spent three weeks.

Patterson, 66, spoke with Reuters about his unprecedented success, his characters and why he thinks his books are so popular.

Q: 'Mistress' was a recent No. 1 bestseller. Is that kind of benchmark getting old, or is it still a surprise?

A: I still get a kick out of it, but I'm not competitive. If it's number one I like that. If it isn't, I'm okay with it. So I can still be the first author and go, 'Wow, I'm published, and there's the book.' And that still is fun. It has never gotten old for me. I can't say it's a surprise. It would be if it wasn't even on the list, I'd go, 'Whaaat? It's not there, oh, we did something wrong.'

Q: Why do you think your books are so popular?

A: The three rules of this kind of fiction for me are story, story, story. I'm telling a story, and I sort of have the sense that I'm talking to one person and I don't want them to get up until I'm finished. And the books are emotional. I think I'm pretty emotional. I think that's one of my strengths and I think that comes through to people.

There are a lot of thrillers that are exciting, but there isn't much humanity to them. I do create characters that people are comfortable with and that they want to know what happened to them next. Even the villains, I think, there's just a humanity to them as diabolical as they may be, there's something recognizably human, which I think is one of the keys to creating villains that are interesting.

Q: When you started out, one assumes it wasn't with a plan or expectation of landing anywhere near where you did in terms of commercial success. What were your hopes at the time?

A: To get published. Just get the book out there. Then the first novel, which was turned down by I think 31 publishers, won an Edgar (book award) as best first mystery, so that was such a surprise and a delight, and for the first time I went, 'I'm actually a writer. I actually have done this thing and I've done it reasonably well.' So that was a real confidence booster.

Q: Did you think then you'd become as prolific as you have?

A: No, that all sort of crept up on me, and then pretty much by accident I wrote a book with a friend of mine Peter de Jonge, a little goth novel 'Miracle on the 17th Green.' It turned out nicely and I liked the process. I think people just don't think through the notion of cooperative art or co-writing. The movie and television worlds are full of teams, so are museums. So it's not as odd as people think it is, but that obviously allowed me to explode the number of books I've involved myself with.

Q: Do you think you'll ever run out of ideas for your books?

A: I don't know, we'll see. I have a big folder of ideas here that's about 9 inches thick. But I would think at a certain point I'm going to cut back on the number of books for sure. But I like to keep experimenting. I've experimented within the kid field, writing some comedy, writing an adventure book with 'Treasure Hunters,' and I have a middle school book about an African American kid in an inner city.

There really aren't a lot of books that star African-American or Hispanic kids and I think that's useful thing to do, where kids can go 'Oh, that kid's like me a little bit.'

Q: Looking 10 or 20 years down the line, do you think you'll want to just keep on writing?

A: Yeah, writing, and then there's just a lot of charity stuff that I'm involved in at this stage. I have over 400 scholarships for teachers, and probably what we're going to do this year is put aside $1 million for independent book stores, where they can come to us and say, 'I need help.' And we continue to mess around with the movies a little bit. So there's plenty of things to play with.