28237
 13190
 39914
 81367
 8554
 61106
 67448
 39004
 22308
 16054
 71468
 60501
 100
 300
 59632
 90783
 5611
 1000
 69475
 69753
 10
 5
 582
 8
 36961
 5071
 20
 53213
 92775
 28738
 100000
 92280
 37944
 9
 2627
 7
 3

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#include <bits/stdc++.h>
using namespace std;
const int INF = 1e9 + 7;
long long n;
long long cnt_divisors(long long x) {
  long long ans = 1;
  for (long long i = 2; i * i <= x; i++) {
    if (x % i == 0) {
      long long cnt = 0;
      while (x % i == 0) {
        x /= i;
        cnt++;
      }
      ans *= (cnt + 1);
    }
  }
  if (x > 2) {
    ans *= 2;
  }
  return ans;
}
int main(void) {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  cin >> n;
  long long mxdivisors = 0;
  long long num;
  for (long long i = n; i >= 2; i--) {
    long long cur = cnt_divisors(i);
    if (cur > mxdivisors) {
      mxdivisors = cur;
      num = i;
    }
  }
  vector<long long> divisors;
  divisors.push_back(num);
  for (long long i = 2; i * i <= num; i++) {
    if (num % i == 0) {
      long long div1 = i, div2 = num / i;
      if (div1 != div2) {
        divisors.push_back(div2);
        long long x = div2;
        while (x * div2 <= num) {
          x *= div2;
          if (num % x) divisors.push_back(x);
        }
      }
      long long x = div1;
      divisors.push_back(div1);
      while (x * div1 <= num) {
        x *= div1;
        if (num % x) divisors.push_back(x);
      }
    }
  }
  sort(divisors.begin(), divisors.end());
  long long ans = 0;
  for (long long i = 0; i < mxdivisors; i++) {
    for (long long j = i + 1; j < mxdivisors; j++) {
      if (divisors[j] % divisors[i] == 0) {
        ans += (divisors[j] / divisors[i]);
      }
    }
  }
  cout << (ans * 4) << '\n';
  return 0;
}
