Simple Huge Time

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Test0_34
{
    class Program
    {
        static void Main(string[] args)
        {
            var a = 1532655487231;
            var b = 7456328877414;
            var c = Math.Abs(a - b);

            Console.WriteLine("Time Between A and B");
            Console.WriteLine("In seconds: {0}", c);
            Console.WriteLine("In minutes: {0}", c / 60);
            Console.WriteLine("In hours: {0}", c / 60 / 60);
            Console.WriteLine("In days: {0}", c / 60 / 60 / 24);
            Console.WriteLine("In weeks: {0}", c / 60 / 60 / 24 / 7);
            Console.WriteLine("In months: {0}", c / 60 / 60 / 24 / 30);
            Console.WriteLine("In years: {0}", c / 60 / 60 / 24 / 365);
            Console.WriteLine("In millenia: {0}", c / 60 / 60 / 24 / 365 / 1000);
            Console.WriteLine("");
            Console.WriteLine("------------------");
            Console.WriteLine("");
            Console.WriteLine("Pretty Print Time");

            Func<long, string> timeToString = t =>
                {
                    var millenia = t / (60L * 60 * 24 * 365 * 1000);
                    t = t % (60L * 60 * 24 * 365 * 1000);
                    var years = t / (60L * 60 * 24 * 365);
                    t = t % (60L * 60 * 24 * 365);
                    var months = t / (60L * 60 * 24 * 30);
                    t = t % (60L * 60 * 24 * 30);
                    var weeks = t / (60L * 60 * 24 * 7);
                    t = t % (60L * 60 * 24 * 7);
                    var days = t / (60L * 60 * 24);
                    t = t % (60L * 60 * 24);
                    var hours = t / (60L * 60);
                    t = t % (60L * 60);
                    var mins = t / (60L);
                    var seconds = t % (60L);

                    return string.Concat(
                     millenia > 0 ? millenia.ToString() : "",
                     millenia > 0 ? " millenia " : "",
                     years > 0 ? years.ToString() : "",
                     years > 0 ? " years " : "",
                     months > 0 ? months.ToString() : "",
                     months > 0 ? " months " : "",
                     weeks > 0 ? weeks.ToString() : "",
                     weeks > 0 ? " weeks " : "",
                     days > 0 ? days.ToString() : "",
                     days > 0 ? " days " : "",
                     hours > 0 ? hours.ToString() : "",
                     hours > 0 ? " hours " : "",
                     mins > 0 ? mins.ToString() : "",
                     mins > 0 ? " minutes " : "",
                     seconds > 0 ? seconds.ToString() : "",
                     seconds > 0 ? " seconds " : ""
                     );
                };

            Console.WriteLine("a {0}", timeToString(a));
            Console.WriteLine("b {0}", timeToString(b));
            Console.WriteLine("c {0}", timeToString(c));
            Console.ReadLine();
        }
    }
}