RIhanna and David Guetta are making their Top 20 debut this week with RiRi's new pumped-up 'Unapologetic' single, 'Right Now.' They come in at No. 20, while Demi Lovato and Mariah Carey up them at No. 18 ('Heart Attack') and No. 16 ('#Beautiful'), respectively.

Check out what else is in store this week on PopCrush's Top 20 countdown below, including a new singer reigning in the No. 1 slot. And be sure to tune in this weekend (Saturday, July 6, and Sunday, July 7) to hear all of these songs, plus more!

Top 20 Songs: Week of July 1 - 7, 2013

20. Rihanna, 'Right Now' Feat. David Guetta
19. Capitol Cities, 'Safe and Sound'
18. Demi Lovato, 'Heart Attack'
17. Anna Kendrick, 'Cups'
16. Mariah Carey, '#Beautiful' Feat. Miguel
15. Ariana Grande, 'The Way' Feat. Mac Miller
14. Maroon 5, 'Love Somebody'
13. Calvin Harris, 'I Need Your Love' Feat. Ellie Goulding
12. Pink, 'Just Give Me a Reason' Feat. Nate Ruess
11. Bruno Mars, 'Treasure'
10. Zedd, 'Clarity' Feat. Foxes
9. Fall Out Boy, 'My Songs Know What You Did in the Dark (Light Em Up)'
8. Jason Derulo, 'The Other Side'
7. Florida Georgia Line, 'Cruise' Feat. Nelly
6. Icona Pop, 'I Love It' Feat. Charli XCX
5. Imagine Dragons, 'Radioactive'
4. Justin Timberlake, 'Mirrors'
3. Robin Thicke, 'Blurred Lines' Feat. Pharrell + T.I.
2. Daft Punk, 'Get Lucky' Feat. Pharell
1. Selena Gomez, 'Come & Get It'

Note: Every Monday, PopCrush will publish a list of our Top 20 songs for that given week. Then, over the weekend, fans can tune in to our national radio show to hear all of these hot songs plus some other amazing pop tunes. To see a list of radio stations where you can hear the PopCrush Top 20 countdown, click here.