#include<fstream>
using namespace std;
unsigned long long int N,P;
unsigned long long int prim(unsigned long long int a,unsigned long long int b)
{unsigned long long int r=a%b;
while(r>0)
{a=b;
b=r;
r=a%b;
}
return b;
}
unsigned long long int fct(unsigned long long int n,unsigned long long int p)
{unsigned long long int i=0,ok=0;
while(ok<p)
{i++;
if(prim(n,i)==1)
ok++;
}
return i;
}
int main()
{ifstream f("frac.in");
ofstream g("frac.out");
f>>N>>P;
g<<fct(N,P);
return 0;
}