let () =
  Scanf.scanf "%d\n" @@ fun n ->
  let ans = ref 0 in
  for c = 1 to n - 1 do
  	let maxn = int_of_float (floor (sqrt (float_of_int (n - c)))) in
  	for a = 1 to maxn do
      if (n - c) mod a = 0 then
      	if (n - c) / a = a then ans := !ans + 1
        else ans := !ans + 2
    done;
  done;
  Printf.printf "%d\n" !ans