Four million is the magic number! Now that Bruno Mars has notched four million followers on Twitter, he has marked the momentous occasion by releasing this video where he thanks and serenades fans! What a charmer. It starts out with Mars solo, then more singers join him, in an escalating harmony -- barbershop quartet-style.

In this black and white clip (shown below), Mars is singing "I got four million followers" with R&B upcomers Liquid Lavender. There are several vocalists in the group and they announce themselves at the end of the clip, in unison, and we're glad they did. They really make this video that much more awesome with their skills and flow.

Mr. Four Million -- that'd be Mars --  is clearly stoked about this digital milestone, singing, "Not one, not two, not three, but four million" and "Can't nobody tell me s--- now!" Retweet that.

Mars ends the with a genuine "Thank you guys" and blows a plethora of kisses at the camera.

If you don't follow Mars on Twitter yet, what are you waiting for? Follow him so that he can get to five million and issue another song and video like this. We want more of these videos.

Watch Bruno Mars Celebrate Four Million Twitter Followers in Song