Pop diva Rihanna scores her sixth million-selling album in the U.S. this week, as her latest release, Unapologetic, sails past the million mark, according to Nielsen SoundScan.

Unapologetic, released late last year, sold another 9,000 (down 17%) in the week ending May 26, bringing its to-date total to slightly more than 1 million. The set — her seventh studio album — also became her first No. 1 on the Billboard 200, following six earlier top 10 entries.

In reaching the threshold in its 27th chart week on the Billboard 200 (falling 33-39 this week), Unapologetic is selling at a faster clip than her previous album, 2011’s Talk That Talk. The latter took 43 frames to reach 1 million.

Of Rihanna’s seven studio releases, all but one have sold a million. Only her debut, 2005’s Music of the Sun, has missed the mark, moving 607,000 to date. Her biggest selling set is 2007’s Good Girl Gone Bad, with 2.8 million. Her total album sales stand at 9.8 million.

Unapologetic has tallied four hit singles on the Billboard Hot 100 chart so far: “Diamonds” (No. 1 for three weeks), “Pour It Up” (19), “Loveeeeeee Song,” featuring Future (55) and “Stay,” featuring Mikky Ekko (3). Her next top 40-focused single is “Right Now” (featuring David Guetta), which is percolating under the threshold of the Pop Songs airplay chart. [Billboard.biz]