// Standard I/O #include #include #include // Standard Library #include #include #include #include // Template Class #include #include #include #include #include #include #include #include // Container Control #include using namespace std; #define rep( i, n ) for( int i = 0; i < n; ++i ) #define irep( i, n ) for( int i = n-1; i >= 0; --i ) #define reep( i, s, n ) for ( int i = s; i < n; ++i ) #define ireep( i, n, s ) for ( int i = n-1; i >= s; --i ) #define foreach(itr, x) for( typeof(x.begin()) itr = x.begin(); itr != x.end(); ++itr) #define mp( a, b ) make_pair( a, b ) #define pb( a ) push_back( a ) #define all( v ) v.begin(), v.end() #define fs first #define sc second #define vc vector // for visualizer.html double SCALE = 1.0; double OFFSET_X = 0.0; double OFFSET_Y = 0.0; #define LINE(x,y,a,b) cerr << "line(" << SCALE*(x) + OFFSET_X << "," \ << SCALE*(y) + OFFSET_Y << "," \ << SCALE*(a) + OFFSET_X << "," \ << SCALE*(b) + OFFSET_Y << ")" << endl; #define CIRCLE(x,y,r) cerr << "circle(" << SCALE*(x) + OFFSET_X << "," \ << SCALE*(y) + OFFSET_Y << "," \ << SCALE*(r) << ")" << endl; typedef long long ll; typedef complex Point; typedef pair pii; typedef pair ipii; typedef vector vi; typedef vector vd; typedef vector< vector > vii; typedef vector< vector > vdd; typedef vector::iterator vi_itr; const int IINF = 1 << 28; const double INF = 1e30; const double EPS = 1e-10; const double PI = acos(-1.0); // Direction : L U R D const int dx[] = { -1, 0, 1, 0}; const int dy[] = { 0, -1, 0, 1 }; bool isprime[2000010]; vector prime; int main() { ll n; cin >> n; reep(i, 2, 2000010) isprime[i] = true; reep(i, 2, 2000010) if( isprime[i] ){ prime.pb(i); for( int j = 2*i; j < 2000010; j+= i ) isprime[j] = false; } set factor; rep(i, prime.size()){ ll tmp = prime[i]; while( n % prime[i] == 0 ){ factor.insert(n / tmp); factor.insert(tmp); n /= prime[i]; tmp *= prime[i]; } } if( factor.size() == 0 ) cout << n << endl; else{ for( auto i : factor ) if( i != 2 ){ cout << i << endl; break; } } }