'21' is No. 1 album for 21st week 1 on the U.S. album chart for a 21st week, Billboard.com reported Wednesday. The album is the longest-running chart topper since "The Bodyguard" soundtrack, featuring music by the late Whitney Houston, spent 20 weeks at No. Houston died Feb. 11, the day before Adele won six Grammy Awards. Houston had been scheduled to attend the music awards ceremony in Los Angeles. 2 on the Billboard 200 is Houston's "Whitney: the Greatest Hits," followed by the "Now 41" compilation CD at No. 3," Adele's "19" at No. 4 and the "2012 Grammy Nominees" album at No. Rounding out the top tier are Van Halen's "A Different Kind of Truth" at No. 6, Paul McCartney's "Kisses on the Bottom" at No. 7, Bruno Mars' "Doo-Wops & Hooligans" at No. 8, Lady Antebellum's "Own the Night" at No. 9 and Civil Wars' "Barton Hollow" at No.