You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named [4-(1,3-benzothiazol-2-ylmethyl)piperazin-4-ium-1-yl]-(5,7-dimethyl-[1,2,4]triazolo[1,5-a]pyrimidin-2-yl)methanone by IUPAC nomenclature, provide its molecular formula.
user
C20H22N7OS+
assistant