As others have stated, Uriel refers to him as little brother and we know he's more powerful because hes at Michael's house. That would lead me to believe he has some sort of angelic powers that are powered by the threshold or at least able to draw on them.
If that is correct then he also is also a mortal and not as restricted, if at all, to how he uses the power, like Uriel and other Angels are. I think this is what scared Anduriel so much in SG.