Beyond Mars's obvious singing ability, the songwriting is far beyond what's going on in 99.9% of pop music. This song is a good example of that, but there are many others. He does do generic pop songs, and I'm not that into those.
The chorus has an abrupt key change which gives it an exciting lift. But then the B section of the chorus transitions back to the new key so seamlessly that you don't even realize it's happened. At the end of the chorus you get an A7 b9/b13, which is the kind of complex and dissonant chord voicing that usually only happens in jazz. It's exciting to me every time it happens. The bridge introduces even more key changes and uses that b9/b13 device as a way of making those repeated changes. The song also ends on a repetition of the bridge section, which is very unusual.
But if you don't get excited by stuff like this, you can just listen to it as a groovy soul song. Anderson .Paak has incredible feel as a drummer. Basically the song works both as a piece of nostalgia-flavored pop and as an elegant jazz composition. It has something for everyone but Zack. I promised three paragraphs, so I'll stop here.