the number of = Who can number? Figure of speech Erotesis (App-6). So with Samaritan Pentateuch and Septuagint. The word "number" is thought by Ginsburg to be an abbreviation of two words = "Who can number? "
me die = my soul die. Hebrew. nephesh. See App-13.
righteous = upright. To die the death of the righteous one must have the righteousness of the righteous.