#include <stdio.h>

long SearchPrimeNumber(long);

void main(void)
{
	long l, h, i;

	long primeSmallNumber, smallFactor = 0, targetNumber = 1;

	scanf("%ld %ld", &l, &h);

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

	printf("%ld\n", targetNumber);
}

long SearchPrimeNumber(long number)
{
	long i;

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

	if (i == number)
		i = 0;

	return i;
}