#include <bits/stdc++.h>

using namespace std;

const int maxc = 50000;
char check[maxc + 1];
vector<int> prime;

void sieve() {
  for (int i = 0; i < maxc; i++)
    check[i] = 1;
  check[0] = 0;
  check[1] = 0;

  for (int i = 2; i * i < maxc; i++)
    if (check[i])
      for (int j = i * i; j < maxc; j += i)
        check[j] = 0;
  for (int i = 2; i < maxc; i++) {
    if (check[i])
      prime.push_back(i);
  }
}

int is_db(int n) {
  int m = n;

  vector<int> factor;
  for (int i = 0; i < prime.size() && prime[i]*prime[i]<=n;i++) {
    while (n % prime[i] == 0) {
      factor.push_back(prime[i]);
      n /= prime[i];
    }
  }
  factor.push_back(n);

  int facsum = 0;
  for (auto i : factor) {
    while (i) {
      facsum += i % 10;
      i /= 10;
    }
  }

  int sum = 0;
  while (m) {
    sum += m % 10;
    m /= 10;
  }
  if (sum == facsum) {
    return 1;
  }
  return 0;
}

int main() {
  int n;
  cin >> n;
  n++;
  sieve();

  while (!is_db(n)) {
    n++;
  }
  cout << n << "\n";
}