From Rigpa Wiki
There are different ways of categorizing the enlightened qualities of a buddha (Tib. སངས་རྒྱས་ཀྱི་ཡོན་ཏན་, Wyl. sangs rgyas kyi yon tan). According to Abhidharma tradition there are eighteen unshared qualities of a buddha, and also thirty-nine qualities exclusive to a buddha. Whereas according to the Abhisamayalankara there are twenty-one sets of immaculate qualities.