include <bits/stdc++.h>

using namespace std; int main() { int n; cin>>n; for(int i=2;i*i<=n;i++) { if(n%i==0) { cout<<i; return 0; }

} 
cout<<n;
}

include <bits/stdc++.h>

using namespace std; int main() { int n; cin>>n; for(int i=2;i*i<=n;i++) { if(n%i==0) { cout<<i; return 0; }

} 
cout<<n;
}

n=int(input()) k=2 o=0 while k*k<=n: if n%k==0: print(k) o+=1 break else: k+=1 if o==0: print(n)