Step 1 : Introduction to the question "Which Beatles song spent 19 weeks on the Billboard chart?"
...The Beatles had a total of 17 songs to hit No. 1 on the Billboard charts. But it was "Hey Jude," released in 1968, that spent a whopping 19 weeks on the charts. It rode the top of the Billboard chart at No. 1 for nine weeks. "Hey Jude's" flip side song, "Revolution," also spent time near the top of the charts. The "Hey Jude" single was the first song released on the Beatle's new Apple label. The Recording Industry Association of America certified "Hey Jude" as a gold record, and it remains a popular song today.Source: BeatlesBible.com