program factorial;
var f : text;
    p,y : longint;
    s,x : real;

begin
    assign(f,'fact.in'); reset(f);
    read(f,p);
    close(f);
    s := 1;
    for y := 1 to p do s := s*10;

    x := 1; y := 1;

    while y < 1000000 do begin
        x := x*y; x := trunc(x) mod trunc(s);
        if trunc(x) mod trunc(s) = 0 then begin
            assign(f,'fact.out'); rewrite(f);
            write(f,y);
            close(f);
            halt;
            end
        else y := y+1;
        end;
    if y = 1000000 then write(f,-1);
    close(f);
end.