using System;
using System.Linq;
using System.Collections.Generic;
using System.IO;

class MyClass
{
    public static void Solve()
    {
        var N = long.Parse(Console.ReadLine());
        var exp = new Dictionary<long, long>();
        long sum = 1;
        if (N % 2 == 0)
        {
            exp.Add(2, 0);
            while (N % 2 == 0)
            {
                N /= 2;
                exp[2]++;
            }
        }
        for (long p = 3; p * p <= N; p += 2)
        {
            if (N % p == 0)
            {
                exp.Add(p, 0);
                while (N % p == 0)
                {
                    N /= p;
                    exp[p]++;
                }
            }
        }
        if (N != 1)
        {
            exp.Add(N, 1);
        }
        foreach (var p in exp.Keys)
        {
            sum *= ((long)Math.Pow(p, exp[p] + 1) - 1) / (p - 1);
        }
        Console.WriteLine(sum);
    }

    public static void Main()
    {
        var sw = new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = false };
        Console.SetOut(sw);
        Solve();
        Console.Out.Flush();
    }
}