var sum,i,N:integer; t,t1:text;
begin
assign (t, 'input.txt'); reset(t);
assign (t1, 'output.txt'); rewrite(t1);
read(t,N);
sum:=0;
for i:=1 to N do
if N mod i = 0 then sum:= sum+i;
write(t1,sum);
close(t1)
end.
