max = 0

def palindrom(number):
	tmp = number
	new = 0
	while(tmp > 0):
		new *= 10
		new += tmp % 10
		tmp = tmp / 10
	
	if new == number:
		return True
	else:
		return False


for i in xrange(100,1000):
	for j in xrange(100,1000):
		if palindrom(i*j) and i*j > max:
			max = i*j

print max