using System;

namespace No371
{
    class Program
    {
        static void Main(string[] args)
        {
            string[] data = Console.ReadLine().Split(' ');
            long l = long.Parse(data[0]);
            long h = long.Parse(data[1]);

            long primeSmallNumber;
            long smallFactor = 0;
            long targetNumber = l;

            for (long i = l; i <= h; i++)
            {
                primeSmallNumber = SearchPrimeNumber(i);
                if (smallFactor <= primeSmallNumber)
                {
                    smallFactor = primeSmallNumber;
                    targetNumber = i;
                }
            }

            Console.WriteLine(targetNumber);
        }

        static long SearchPrimeNumber(long number)
        {
            long i = 0;

            for (i = 2; i < number; i++)
                if (number % i == 0)
                    break;

            if (i == number) i = 0;

            return i;
        }
    }
}