public static void main(String[] args) throws Exception {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
int time = Integer.parseInt(br.readLine());
int sum = 0;
for (int i = 1; i < time; i++) {
if (time % i == 0)
sum += i;
}
if (sum == time)
System.out.println("yes");
else
System.out.println("no");