ls sorts filenames strictly lexicographically, comparing character by character, so e.g. "055436307" is compared as the characters "0", "5", "5", etc. so it sorts before "121134" because "0" is less than "1". if all compared characters match and one string ends, the shorter one comes first. Symbols like _ are just more characters, and their position relative to digits depends on the locale’s collation table.

Google Drive uses ICU collation with the numeric option enabled, which treats each consecutive sequence of digits inside the filename as an integer. so "055436307" is parsed as the number 55,436,307, while "121134" is parsed as 121,134. and since 121,134 < 55,436,307 then "121134..." comes before "055436307..." even though lexicographic order would suggest the opposite. and i think when two digit runs have the same numeric value, the shorter run comes first; if runs are equal and the string continues, then normal character comparison resumes, including any underscores or suffixes