The song comes from Mars' latest album, "Unorthodox Jukebox," and follows the album's first single "Locked Out Of Heaven," which was No. 1 for six consecutive weeks earlier this year.

"When I Was Your Man" was also Mars' sixth single to claim the No. 1 spot on Billboard's "Mainstream Top 40" radio airplay chart. That places Mars ahead of Justin Timberlake and Nelly as the solo male artist with the most No. 1's on the chart's 20-year history. You can watch a performance of the song from the Ellen DeGeneres Show here.