In an ad for Powell's books:
19 is the atomic number of potassium. The Backstreet Boys are 19 years old. 19 is the eighth smallest prime number. In binary, the number 19 loos like 10112. In miniature golf, the golfer wins an instant prize on the 19th hole. According to certain religious texts, there are 19 angels guarding hell. You could win 19 free signed books from Powell's.com if you enter our Signed Editions contest.
To enter the contest: powell's 19 books sweepstakes