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#include <bits/stdc++.h>
using namespace std;
long long cmmdc(long long a,long long b)
{
long long r;
while(b)
{
r=a%b;
a=b;
b=r;
}
return a;
}
int v[155];
int cnt;
long long a[15][2000];
int main()
{
freopen("frac.in","r",stdin);
freopen("frac.out","w",stdout);
long long n ,k;
scanf("%lld%lld",&n,&k);
long long r=n,t1=n;
long long d=2,e=0;
while(d*d<=r)
{
while(r%d==0)
{
e++;
r/=d;
}
if(e)t1*=(d-1),t1/=d;
if(e)v[++cnt]=d;
d++;
e=0;
}
if(r>1)
t1*=(r-1),v[++cnt]=r,t1/=r;
k--;
long long sol=(k/t1)*n;
k%=t1;
k++;
long long prod=1;
int nr=(1<<cnt);
int i;
for(i=1;i<nr;i++)
{
prod=1;
int c=0;
int j;
for(j=0;j<cnt;j++)
{
if(i&(1<<j))
{
c++;
prod*=v[cnt-j];
}
}
a[c][++a[c][0]]=prod;
}
long long st=1,dr=n;
long long l=0;
while(st<=dr)
{
long long med=(st+dr)/2;
long long nr1=med;
for(int i=1;i<=13;i++)
{if(a[i][0]==0)break;
int j;
for(j=1;j<=a[i][0];j++)
if(i%2==0)nr1+=med/a[i][j];
else
nr1-=med/a[i][j];
}
if(nr1<k)st=med+1;
if(nr1>k)dr=med-1;
if(nr1==k)
{
l=med;
dr=med-1;
}
}
sol+=l;
printf("%lld\n",sol);
return 0;
}