A look at Spears' top-selling digital and physical singles, plus quirky chart feats, courtesy of knowledgeable 'Ask Billboard' readers.
Ask Billboard is updated every week. As always, submit your questions about Billboard charts, sales and airplay, as well as general music musings, to email@example.com. Please include your first and last name, as well as your city, state and country, if outside the U.S.
LITTLE 'KNOW'N FACTS
Some fun charts odds and ends for you and Billboard readers: