#include <bits/stdc++.h>
#define ll long long int
using namespace std;
int const MAXN=2e7+500;
  map<int,int> mp;
  int p[MAXN];
  vector <int> v;
  void ff (int n){
      set <int> s;
     int pf_idx=0,pf=v[pf_idx];
     while (pf*pf<=n){
        while (n%pf==0) {n/=pf, s.insert(pf); };
        pf=v[++pf_idx];
     }
     if (n!=1) s.insert(n);
     for (auto cur :  s) mp[cur]++;

  }
int main (){
 ios_base::sync_with_stdio(0);
  cin.tie(0);
//freopen("input.txt","r",stdin);
  int n;
  cin>>n;
  int g=0;
  int a[n];
  for (int i=0;i<n;i++){
     cin>>a[i];
     g=__gcd(g,a[i]);
  }
  int ans=1e9;
  for (int i=0;i<n;i++) a[i]/=g;

  for (int i=2;i<MAXN;i++)
  if (p[i]==0){
    v.push_back(i);
     for (int j=2*i;j<MAXN;j+=i)
         p[j]=1;
  }
  for (int i=0;i<n;i++) ff(a[i]);

  for (auto cur : mp){
     if (cur.first!=1)
        ans=min(ans,n-cur.second);

  }

if (ans ==1e9) cout<<-1;
else cout<<ans;

}