#include <iostream>
using namespace std;
int main(){
int sumapar=0, sumaimpar=0, n, i;
cin>>n;
for(i=2;i<=n/2;i++)
if(n%i==0)
if(i%2==0) sumapar = sumapar+i;
else sumaimpar = sumaimpar+i;
if(sumapar==0) cout<<"Nu exista";
else cout<<(sumaimpar/sumapar);
}