#include <bits/extc++.h>
#include <atcoder/all>

using namespace std;
using ll = long long;
#define REP(i,n) for(int i=0;i<int(n);i++)
#define FOR(i,a,b) for(int i=a;i<=int(b);i++)
#define ALL(x) x.begin(),x.end()
#define INF INT_MAX
#define INFL LLONG_MAX / 4
using namespace atcoder;
using mint = modint998244353;
template<typename T> void chmin(T& a, T b) { a = min(a, b); }
template<typename T> void chmax(T& a, T b) { a = max(a, b); }
#define PR(x) cerr << #x << "=" << x << endl
using i128 = __int128_t;

int main() {
  ll n;
  cin >> n;
  ll ans = n;
  map<ll, ll> mp;
  for(ll i = 2; i*i <= n; i++) {
    while(n % i == 0) {
      n /= i;
      mp[i]++;
    }
  }
  if(n > 1) mp[n]++;
  ll del = 1;
  for(auto [x, cnt]: mp) {
    del *= cnt + 1;
  }

  cout << ans - del;
  return 0;
}