var z,n,p,x:longint; cinci,cinci2,cinci3:longint;  ok:boolean;
    f:text;
begin
assign(f,'fact.in');reset(f);
read(f,p);close(f);
n:=5;cinci:=0; cinci2:=0;cinci3:=0;
while (cinci+cinci2+cinci3)<p do begin
x:=n;
while x mod 5 = 0 do begin inc(cinci);x:=x div 5; end;
inc(n,5);
if cinci<0 then begin cinci2:=cinci+1;cinci:=1;end;
if cinci2<0 then begin cinci3:=cinci2+1;cinci2:=1;end;
end;
dec(n,5);
if p=0 then n:=1;
assign(f,'fact.out');rewrite(f);
write(f,n);
close(f);

end.