#include using namespace std; template inline bool chmax(T &a, T b) { if(a < b) { a = b; return 1; } return 0; } template inline bool chmin(T &a, T b) { if(a > b) { a = b; return 1; } return 0; } #define DEBUG #ifdef DEBUG template ostream &operator<<(ostream &os, const pair &p) { os << '(' << p.first << ',' << p.second << ')'; return os; } template ostream &operator<<(ostream &os, const vector &v) { os << '{'; for(int i = 0; i < (int)v.size(); i++) { if(i) { os << ','; } os << v[i]; } os << '}'; return os; } void debugg() { cerr << endl; } template void debugg(const T &x, const Args &... args) { cerr << " " << x; debugg(args...); } #define debug(...) \ cerr << __LINE__ << " [" << #__VA_ARGS__ << "]: ", debugg(__VA_ARGS__) #define dump(x) cerr << __LINE__ << " " << #x << " = " << (x) << endl #else #define debug(...) (void(0)) #define dump(x) (void(0)) #endif struct Setup { Setup() { cin.tie(0); ios::sync_with_stdio(false); cout << fixed << setprecision(15); } } __Setup; using ll = long long; #define ALL(v) (v).begin(), (v).end() #define RALL(v) (v).rbegin(), (v).rend() const int INF = 1 << 30; const ll LLINF = 1LL << 60; constexpr int MOD = 1000000007; const int dx[4] = {1, 0, -1, 0}; const int dy[4] = {0, 1, 0, -1}; //------------------------------------- vector divisor(ll n) { vector ret; for(ll i = 1; i * i <= n; i++) { if(n % i == 0) { ret.push_back(i); if(i * i != n) ret.push_back(n / i); } } sort(begin(ret), end(ret)); return (ret); } int main() { ll N; cin >> N; N *= 2; auto v = divisor(N); for(ll n : v) { ll a = N / n; if((a - (n - 1)) % 2 == 0 && (a - n + 1) > 0) { cout << "YES\n"; return 0; } } cout << "NO\n"; }