using System; using System.Collections.Generic; using System.Linq; using System.Linq.Expressions; using System.IO; using System.Threading; using System.Text; using System.Diagnostics; using static util; using P = pair; using CALC = System.Func; using FU = System.Func; using APPLY = System.Func, int, int ,int[]>; using MERGE = System.Func, System.Func, System.Func>; using Binary = System.Func; using Unary = System.Func; class Program { static StreamWriter sw = new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = false }; static Scan sc = new Scan(); const int M = 1000000007; const int M2 = 998244353; const long LM = 1L << 60; const double eps = 1e-11; static void DBG(string a) => Console.WriteLine(a); static void DBG(IEnumerable a) => DBG(string.Join(" ", a)); static void DBG(params object[] a) => DBG(string.Join(" ", a)); static void Prt(string a) => sw.WriteLine(a); static void Prt(IEnumerable a) => Prt(string.Join(" ", a)); static void Prt(params object[] a) => Prt(string.Join(" ", a)); static void Main(string[] args) { var solver = new Solver(); // var t = new Thread(solver.solve, 1 << 26); // 64 MB // t.Start(); // t.Join(); solver.solve(); sw.Flush(); } class Solver { public void solve() { var n = sc.Long; long ans = 0; for (long i = 1; i * i <= n; i++) { if (n % i == 0) { ans += i; if (n / i != i) ans += n / i; } } Prt(ans); } // end Solver.solve } } class pair : IComparable> { public T v1; public U v2; public pair() : this(default(T), default(U)) {} public pair(T v1, U v2) { this.v1 = v1; this.v2 = v2; } public int CompareTo(pair a) { int c = Comparer.Default.Compare(v1, a.v1); return c != 0 ? c : Comparer.Default.Compare(v2, a.v2); } public override string ToString() => v1 + " " + v2; public void Deconstruct(out T a, out U b) { a = v1; b = v2; } public static bool operator>(pair a, pair b) => a.CompareTo(b) > 0; public static bool operator<(pair a, pair b) => a.CompareTo(b) < 0; public static bool operator>=(pair a, pair b) => a.CompareTo(b) >= 0; public static bool operator<=(pair a, pair b) => a.CompareTo(b) <= 0; } static class util { public static pair make_pair(T v1, U v2) => new pair(v1, v2); public static T sq(T a) => Operator.Multiply(a, a); public static T Max(params T[] a) => a.Max(); public static T Min(params T[] a) => a.Min(); public static bool inside(int i, int j, int h, int w) => i >= 0 && i < h && j >= 0 && j < w; static readonly int[] dd = { 0, 1, 0, -1 }; static readonly string dstring = "RDLU"; public static P[] adjacents(this P p) => adjacents(p.v1, p.v2); public static P[] adjacents(this P p, int h, int w) => adjacents(p.v1, p.v2, h, w); public static pair[] adjacents_with_str(int i, int j) => Enumerable.Range(0, dd.Length).Select(k => new pair(new P(i + dd[k], j + dd[k ^ 1]), dstring[k])).ToArray(); public static pair[] adjacents_with_str(int i, int j, int h, int w) => Enumerable.Range(0, dd.Length).Select(k => new pair(new P(i + dd[k], j + dd[k ^ 1]), dstring[k])) .Where(p => inside(p.v1.v1, p.v1.v2, h, w)).ToArray(); public static P[] adjacents(int i, int j) => Enumerable.Range(0, dd.Length).Select(k => new P(i + dd[k], j + dd[k ^ 1])).ToArray(); public static P[] adjacents(int i, int j, int h, int w) => Enumerable.Range(0, dd.Length).Select(k => new P(i + dd[k], j + dd[k ^ 1])).Where(p => inside(p.v1, p.v2, h, w)).ToArray(); public static void Assert(bool cond) { if (!cond) throw new Exception(); } public static Dictionary compress(this IEnumerable a) => a.Distinct().OrderBy(v => v).Select((v, i) => new { v, i }).ToDictionary(p => p.v, p => p.i); public static Dictionary compress(params IEnumerable[] a) => compress(a.Aggregate(Enumerable.Union)); public static T[] inv(this Dictionary dic) { var res = new T[dic.Count]; foreach (var item in dic) res[item.Value] = item.Key; return res; } public static void swap(ref T a, ref T b) where T : struct { var t = a; a = b; b = t; } public static void swap(this IList a, int i, int j) where T : struct { var t = a[i]; a[i] = a[j]; a[j] = t; } public static T[] copy(this IList a) { var ret = new T[a.Count]; for (int i = 0; i < a.Count; i++) ret[i] = a[i]; return ret; } } static class Operator { static readonly ParameterExpression x = Expression.Parameter(typeof(T), "x"); static readonly ParameterExpression y = Expression.Parameter(typeof(T), "y"); public static readonly Func Add = Lambda(Expression.Add); public static readonly Func Subtract = Lambda(Expression.Subtract); public static readonly Func Multiply = Lambda(Expression.Multiply); public static readonly Func Divide = Lambda(Expression.Divide); public static readonly Func Plus = Lambda(Expression.UnaryPlus); public static readonly Func Negate = Lambda(Expression.Negate); public static Func Lambda(Binary op) => Expression.Lambda>(op(x, y), x, y).Compile(); public static Func Lambda(Unary op) => Expression.Lambda>(op(x), x).Compile(); } class Scan { StreamReader sr; public Scan() { sr = new StreamReader(Console.OpenStandardInput()); } public Scan(string path) { sr = new StreamReader(path); } public int Int => int.Parse(Str); public long Long => long.Parse(Str); public double Double => double.Parse(Str); public string Str => sr.ReadLine().Trim(); public pair Pair() { T a; U b; Multi(out a, out b); return new pair(a, b); } public P P => Pair(); public int[] IntArr => StrArr.Select(int.Parse).ToArray(); public long[] LongArr => StrArr.Select(long.Parse).ToArray(); public double[] DoubleArr => StrArr.Select(double.Parse).ToArray(); public string[] StrArr => Str.Split(new[]{' '}, StringSplitOptions.RemoveEmptyEntries); bool eq() => typeof(T).Equals(typeof(U)); T ct(U a) => (T)Convert.ChangeType(a, typeof(T)); T cv(string s) => eq() ? ct(int.Parse(s)) : eq() ? ct(long.Parse(s)) : eq() ? ct(double.Parse(s)) : eq() ? ct(s[0]) : ct(s); public void Multi(out T a) => a = cv(Str); public void Multi(out T a, out U b) { var ar = StrArr; a = cv(ar[0]); b = cv(ar[1]); } public void Multi(out T a, out U b, out V c) { var ar = StrArr; a = cv(ar[0]); b = cv(ar[1]); c = cv(ar[2]); } public void Multi(out T a, out U b, out V c, out W d) { var ar = StrArr; a = cv(ar[0]); b = cv(ar[1]); c = cv(ar[2]); d = cv(ar[3]); } public void Multi(out T a, out U b, out V c, out W d, out X e) { var ar = StrArr; a = cv(ar[0]); b = cv(ar[1]); c = cv(ar[2]); d = cv(ar[3]); e = cv(ar[4]); } }