If the pace of book sales predicts a movie's success, then "The Da Vinci Code" is a certain smash.

In less than two months, Dan Brown's blockbuster thriller has sold nearly 3 million copies in paperback as anticipation grows for the film, starring Tom Hanks and coming out Friday. An original printing of 5 million, the highest in recent memory for a paperback, has been raised to 6.3 million.

Since the hardcover was released, in March 2003, the novel has sold 60 million copies worldwide. All of those books form a bulk great enough, according to the publisher, to cover all of Chicago in paper or outweigh 90 Boeing 747 jumbo jets.

And the end is not in sight.

"Sales are growing dramatically week to week, we're reprinting to keep up with demand, and the biggest months are still ahead of us," Anne Messitte, publisher of Vintage-Anchor Books, a paperback imprint of Random House, Inc., said in a statement Tuesday.