Charles T. Fritsch and Rolland W. Schloerb, “Proverbs,” in Interpreter’s Bible, vol. 4, p. 954, headnote to 31:10–31: “By this device the writer may be indicating that he is dealing exhaustively with the subject in an orderly way.”
In fact, Patrick Skehan has argued in a number of studies that even the alphabetic number 22 was recognized as a sign of completeness and became an organizing principle for poems (see the references in n. 1). Freedman (The Unity of the Hebrew Bible [Ann Arbor: Univ. of Michigan Press, 1991], pp. 81–82) sees alphabetic numbers playing an organizational role in the overall structure of the Hebrew Bible.