#include <bits/stdc++.h>

using namespace std;

const long long B = 1e6;

bool c[5 + B];
vector <long long> v;
vector <long long> mu;

void ciur()
{
    for(long long i = 2; i <= B; i++)
    {
        if(c[i] == false)
            for(long long j = i * i; j <= B; j+= i)
                c[j] = true;
    }
    for(long long i = 2; i <= B; i++)
        if(c[i] == false)
            v.push_back(i);
}

long long solve(long long a, long long b)
{
    mu.clear();
    for(auto x : v)
    {
        if(x * x > b) continue;

        if(x <= b && b % x == 0) mu.push_back(x);
        while(b % x == 0) b /= x;
    }
    if(b > 1) mu.push_back(b);
    long long rez(0);
    for(long long i = 1; i < (1LL << mu.size()); i++)
    {
        long long nr(0), p(1);
        for(long long j = 0; j < mu.size(); j++)
        {
            if(i & (1LL << j))
            {
                nr++;
                p *= mu[j];
            }
        }

        if(nr % 2 == 0) rez -= (a / p);
        else rez += (a / p);
    }

    return a - rez;
}

int main()
{
    freopen("frac.in", "r", stdin);
    freopen("frac.out", "w", stdout);
    ciur();

    long long m, a, b;
    scanf("%lld%lld", &a, &b);
    long long r, pas;
    r = 0;
    pas = 1LL << 50;
    while(pas)
    {
        if(solve(r + pas, a) < b)
            r += pas;
        pas >>= 1;

    }
    printf("%lld\n", r + 1);
    return 0;
}