#include <bits/stdc++.h>
using namespace std;

signed main() {
  ios::sync_with_stdio(false);

  int N;
  cin >> N;

  vector<bool> np(N + 1);
  vector<int> primes;
  vector<int> maxpf(N + 1);
  for (int i = 2; i < np.size(); ++i) {
    if (np[i]) continue;
    primes.emplace_back(i);
    maxpf[i] = i;
    for (int j = i + i; j < np.size(); j += i) {
      np[j] = 1;
      maxpf[j] = max(maxpf[j], i);
    }
  }

  int ni = upper_bound(primes.begin(), primes.end(), N) - primes.begin();
  int si = 0;
  while (primes[si] * primes[si] <= N) ++si;

  vector<vector<int>> dp(ni + 1, vector<int>(1 << si));
  for (int i = 0; i < ni; ++i) {
    dp[~i & 1] = dp[i & 1];
    for (int j = 2; j <= N; ++j) {
      if (maxpf[j] != primes[i]) continue;
      int t = 0;
      for (int k = 0; k < si; ++k)
        if (j % primes[k] == 0) t |= 1 << k;
      for (int s = 0; s < 1 << si; ++s)
        if ((s & t) == 0) dp[~i & 1][s | t] = max(dp[~i & 1][s | t], dp[i & 1][s] + j);
    }
  }

  cout << *max_element(dp[ni & 1].begin(), dp[ni & 1].end()) << endl;
}