Master Numbers

/*
A master number is an integer that holds the following properties:
• Is symmetric (palindrome), e.g. 5, 77, 282, 14341, 9553559.
• Its sum of digits is divisible by 7, e.g. 77, 313, 464, 5225, 37173.
• Holds at least one even digit, e.g. 232, 707, 6886, 87578.

Write a program to print all master numbers in the range [1…n].
*/

namespace Master_Numbers
{
    using System;

    internal static class MasterNumberFinder
    {
        private static void Main()
        {
            var n = int.Parse(Console.ReadLine());

            for (int i = 7; i <= n; i++)
            {
                var digitsSum = SumOfDigits(i);
                if (IsPalindrome(i) && DigitsSumIsDivisibleBy7(digitsSum)
                    && ContainsEvenDigit(i))
                {
                    Console.WriteLine(i);
                }
            }
        }

        private static bool IsPalindrome(int num)
        {
            var numStr = num.ToString();
            for (int i = 0; i < numStr.Length / 2; i++)
            {
                if (numStr[i] != numStr[numStr.Length - 1 - i])
                {
                    return false;
                }
            }

            return true;
        }

        private static int SumOfDigits(int num)
        {
            var sum = 0;
            var number = num;
            while (number >= 1)
            {
                sum += number % 10;
                number /= 10;
            }

            return sum;
        }

        private static bool DigitsSumIsDivisibleBy7(int sum)
        {
            if (sum % 7 == 0)
            {
                return true;
            }
            else
            {
                return false;
            }
        }

        private static bool ContainsEvenDigit(int num)
        {
            var number = num;
            while (number > 1)
            {
                var nextDigit = number % 10;
                if (nextDigit % 2 == 0)
                {
                    return true;
                }

                number /= 10;
            }

            return false;
        }
    }
}