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#include<bits/stdc++.h>
using namespace std;
int st[105],dd;
long long d[15],mid;
long long dc,n,p;
long long ls,ld,sol;
pair<long long,long long> comb[1<<15];
void add(int p)
{
long long pr=1;
long long nr=0;
for(int i=1;i<=p;i++)
{
if(st[i])
{
pr=pr*d[i];
nr=nr+1LL;
}
}
if(!nr) return;
dc++;
comb[dc].first=pr;
comb[dc].second=nr;
}
void bktr(int p)
{
for(int i=0;i<=1;i++)
{
st[p]=i;
if(p==dd)
{
add(p);
}
else
if(p<dd) bktr(p+1);
}
}
long long f(long long x)
{
long long el=0;
for(int i=1;i<=dc && comb[i].first<=x;i++)
{
if((comb[i].second%2))
{
el=el+(x/comb[i].first);
}
else
el=el-(x/comb[i].first);
}
return x-el;
}
int main()
{
freopen("frac.in","r",stdin);
freopen("frac.out","w",stdout);
scanf("%lld%lld",&n,&p);
for(int i=2;(i*i)<=n && n>1;i++)
{
if(!(n%i))
{
d[++dd]=i;
while(!(n%i)) n/=i;
}
}
if(n>1)
{
d[++dd]=n;
}
bktr(1);
ls=1;
ld=1;
for(int i=1;i<=61;i++) ld<<=1;
sol=0;
while(ls<=ld)
{
mid=ls+((ld-ls)>>1);
if(f(mid)>=p)
{
sol=mid;
ld=mid-1;
}
else ls=mid+1;
}
printf("%lld\n",sol);
return 0;
}