program alex;
var f,g:text;
    p,h,j,i,d:longint;
begin
assign(f,'fact.in');reset(f);
readln(f,p);
close(f);
assign(g,'fact.out');rewrite(g);
if p=0 then write(g,1)
       else begin
            d:=0;
            i:=0;
            j:=0;
            while d<p do
                  begin
                  i:=i+5;
                  j:=i;
                  while(j mod 5=0)do
                          begin
                          d:=d+1;
                          j:=j div 5;
                          end;
                  end;
            if d>p then begin
                        j:=i-((d-p)*5);
                        write(g,j);
                        end
                   else write(g,i);
            end;
close(g);
end.