var p,n5,x,xx,nrzero:longint;
    f:text;
begin
assign(f,'fact.in');
reset(f);
readln(f,p);
Close(f);
if p=0
 then
  begin
  assign(f,'fact.out');
  rewrite(f);
  writeln(f,1);
  close(f);
  end
 else
  begin
   n5:=0;
   x:=0;
   nrzero:=0;
   while (nrzero<>p)  do
    begin
      inc(x,5);
      if (x=maxlongint)
       then
         begin
           assign(f,'fact.out');
           rewrite(f);
           write(f,-1);
           close(f);
           break;
         end;
      {xx:=x;
       while xx mod 5=0 do
       begin
        inc(n5);
        xx:=xx div 5;
       end;       }
      inc(nrzero);
    end;
   assign(f,'fact.out');
   rewrite(f);
   if (nrzero=p)  then
     begin
   write(f,x);
   close(f);
   end;
  end;
end.