K-pop supergroup BTS has sold more than 4 million copies of its new album "Arirang" on the first day of release, marking the band's highest first-day sales to date, its agency said Saturday. BigHit Music said the band's fifth studio album recorded 3.98 million sales in 24 hours after its release on Friday. The figure surpasses the group's previous first-week record of 3.37 million copies set by its fourth studio album "Map of the Soul: 7" in February 2020. "Arirang" has also topped iTunes' Top A