#include <iostream>
#include <fstream>

using namespace std;

long long find(long long P, long long Q){
    long long fact = 1;
    for(long long i = 1; i <= INT32_MAX; i++ )
    {
        fact = fact * i;
        while(fact % P == 0)
        {
            Q--;
            fact = fact/P;
        }

        if(Q == 0)
        {
            return i;
        }
    }
    return -1;
}

int main() {
    long long P,Q;

    freopen("gfact.in", "r", stdin);
    freopen("gfact.out", "w", stdout);

    scanf("%lld",&P);
    scanf("%lld",&Q);

    printf("%lld",find(P,Q));

    return 0;
}