Rihanna would still need to score nine Number One hits to break the record. She currently has 12 Number Ones and the Beatles had 20. But Rihanna has a few things going for her the Fab Four never did.
1. She's a solo artist, not a band.
The reason the Beatles stopped racking up Number Ones was because they broke up and stopped recording together. Throughout the 1970s and 1980s, former Beatles scored an additional 16 Number Ones as solo artists (or in Paul McCartney's case, with his new band, Wings), but none of those songs count in their total. Rihanna won't ever have to worry about this.
2. She frequently collaborates with other artists.
Two of Rihanna's Number Ones — Eminem's "Love The Way You Lie" and T.I.'s "Live Your Life" — were other artist's songs that she was featured on, but they still count as her Number Ones too. Collaborations were extremely rare during the 1960s but are pretty much omnipresent today and benefit an artist like Rihanna who has worked with a diverse mix of artists ranging from Coldplay to Britney Spears to Young Jeezy. Which leads to the next point...
3. She's a big tent artist in a pop world full of niche acts.
Many artists are pegged to a single genre, which means shifts in popular music can hamper their chart fortunes. Rihanna has wisely been positioned as more versatile. For example, her current Number One, "Diamonds," has become a Top 10 hit on a number of Billboard's genre charts like Hot Dance Club Songs, Pop Songs and Hot R&B/Hip-Hop Songs.
4. She knows how to game the system.
Rihanna was poised to score her tenth Number One in the spring of 2011 with "S&M," but it was stalling on the charts. It had been stuck at Number Two for three weeks, and while radio airplay was strong, digital sales had begun to cool. Def Jam knew it had to act quick before the song's window of opportunity closed. A remix featuring Britney Spears was hastily recorded and released, providing enough of a sales increase that the song reached Number One for a week. Digital music makes it easier for artists and record labels to release special remixes or sell a song at a discounted price if it needs a quick boost in the charts.