var o,i,m,x:integer;
f,g:text;
function p5(x:integer):integer;
var i:integer;
begin
i:=0;
while x>5 do begin
             x:=x div 5;
             inc(i);
             end;
p5:=i;
end;
function nr0(x:integer):integer;
var i,p,m:integer;
begin
p:=0;
m:=5;
for i:=1 to p5(x) do begin
                     p:=p+trunc(x/m);
                     m:=m*5;
                     end;
nr0:=p
end;
BEGIN
assign(f,'fact.in');
reset(f);
readln(f,o);
close(f);
i:=5;m:=0;
while nr0(i)<o do begin
                 inc(m);
                 i:=i*5;
                 end;
i:=i div 5;
x:=i;
while nr0(x)<o do x:=x+5;
assign(g,'fact.out');
rewrite(g);
if nr0(x)=o then write(g,x);
close(g);
end.