#include<stdio.h>
#define pmax 230580000000
int fac[100000],t[pmax];
long long n,p,l;

void desc()
{long long i;
for(i=2;i<=n;++i)
	if(!(n%i)) {while(!(n%i)) n/=i;
				fac[l++]=i;} }

void gen()
{long long i,j,max=2000;
for(i=0;i<l;++i)
	for(j=1;fac[i]*j<max;++j)
		t[j*fac[i]]=1;}

int main()
{long long i=0,nr=0;
freopen("frac.in","r",stdin);
freopen("frac.out","w",stdout);
scanf("%lld%lld",&n,&p);
desc();
gen();
for(i=1;nr<p;++i)
	if(!t[i]) ++nr;
printf("%lld\n",i-1);
fclose(stdin);
fclose(stdout);
return 0;}