program bt;
uses crt;
var n, i: integer;
begin
clrscr;
readln(n);
if n <= 1 then writeln(n,'day khong phai la so nguyen to');
else
begin
i:=2;
while (n mod i<>0) do i:= i+1;
if i = n then writeln(n,'day la so nguyen to');
else writeln(n,'day khong phai la so nguyen to');
end;
readln;
end.