#include <stdio.h>
int main(){
    long long  fact[1000000],i,j,n,p,d,nr;
    FILE*in  = fopen("frac.in", "r");
    FILE*out = fopen("frac.out","w");

    fscanf(in,"%lld%lld",&n,&p);
    d = 2;i=1;
    while (n>1){
	  if(n%d==0)fact[++i] = d;
	  while(n%d == 0) n/=d;
	  d++;
    }
    n = i; i = 1; nr = 1;

    while (nr<=p){
	  for (j = 2;j<=n;j++)
	      if(i%j == 0) break;
	     // else if(j%i == 0 && i<=j) break;
	  if(j == n+1)nr++;
	  i++;
    }
    fprintf(out,"%lld",i-1);
    return 0;
}