using System;

class GreatestCommonDivisor
{
    static void Main(string[] args)
    {
        int a = int.Parse(Console.ReadLine());
        int b = int.Parse(Console.ReadLine());
        int commonDivisor = Math.Min(a, b);
        bool isPrime = false;
        while (commonDivisor >= 3)
        {
            if (a % commonDivisor == 0 && b % commonDivisor == 0)
            {
                for (int divider = 2; divider <= Math.Sqrt(commonDivisor); divider++)
                {
                    if (commonDivisor % divider == 0)
                    {
                        Console.Write(commonDivisor + " ");
                        isPrime = false;
                        break;
                    }
                }
            }
            commonDivisor--;
        }
        if (!isPrime)
        {
            Console.WriteLine(-1);
        }
    }
}