#include <bits/stdc++.h>
using namespace std;
unsigned long long k=3, p, n;
vector <unsigned long long> divs;
ifstream in("frac.in");
ofstream out("frac.out");
bool check(unsigned long long nr)
{
    for(int i=0;i<divs.size() && divs[i]<=nr;i++) if(nr%divs[i]==0) return 0;
    return 1;
}
int main()
{
    in>>n>>p;
    if(n%2==0)
    {
        divs.push_back(2);
        while(n%2==0) n/=2;
    }
    while(k<=n)
    {
        if(n%k==0)
        {
            divs.push_back(k);
            while(n%k==0) n/=k;
        }
    }
    for(int j=0,k=1;j<=p;)
    {
        if(j==p)
        {
            out<<k-1<<" ";
            return 0;
        }
        if(check(k)) j++;
        k++;
    }
    return 0;
}