Where does “число” come from?
число (Russian) comes from Old East Slavic число, from Proto-Slavic čislo, from Proto-Slavic čisti, from Proto-Balto-Slavic (s)keistéi, from Proto-Indo-European *(s)kʷéyt-t ~ *(s)kit-ént, from Proto-Indo-European kʷeyt- — to notice; to read.
число (Russian): number; count; number
Ancestry of “число”, step by step
Words derived from “число”