#include <bits/stdc++.h>

using namespace std;
#define int long long int
#define N 1000006

bool ciur[N];
int n, p, st, dr, mij, ans;
vector <int> prime, f;

void eratostene() {
    ciur[0] = ciur[1] = 1;
    for (int i = 2; i * i < N; i++)
        if (!ciur[i])
            for (int j = 2; j * i < N; j++)
                ciur[i * j] = 1;
    for (int i = 2; i < N; i++)
        if (!ciur[i])
            prime.emplace_back(i);
}

void ia_factorii_primi(int b) {
    int d = prime[0];
    int l = 0;
    while (b > 1 && d * d <= b) {
        if (b % d == 0) {
            f.emplace_back(d);
            while (b % d == 0)
                b /= d;
        }
        d = prime[++l];
    }
    if (b > 1)
        f.emplace_back(b);
}

int pinex(int up_bound) {
    /// functia asta imi returneaza numarul de numere prime cu n in intervalul [1...up_bound]
    int neprime = 0;
    for (int mask = 1; mask < (1 << f.size()); mask++) {
        int nr_biti = __builtin_popcountll(mask);
        int intersectie = 1;
        for (int k = 0; k < f.size(); k++) {
            if (mask & (1 << k)) {
                intersectie *= f[k];
            }
        }
        int big_jonathan = n / intersectie;
        if (nr_biti % 2)
            neprime += big_jonathan;
        else
            neprime -= big_jonathan;
    }
    return up_bound - neprime;
}

int pw(int a, int n) {
    if (!n)
        return 1;
    else {
        if (n % 2)
            return a * pw(a, n-1);
        else {
            int c = pw(a, n/2);
            return c * c;
        }
    }
}

signed main()
{
    freopen("frac.in", "r", stdin);
    freopen("frac.out", "w", stdout);
    cin.tie(0)->sync_with_stdio(false);
    cin >> n >> p;
    eratostene();
    ia_factorii_primi(n);
    st = 1;
    dr = pw(2, 61);
    while (st <= dr) {
        mij = st + (dr - st)/2;
        if (pinex(mij) >= p)
            ans = mij, dr = mij - 1;
        else
            st = mij + 1;
    }
    cout << ans;
    return 0;
}