# coding: utf-8


import math


def sum_digits(n):
    sum = 0
    while n > 0:
        sum += n % 10
        n = int(n / 10)
    return sum


def is_prime(n):
    if n % 2 == 0 and n > 2: 
        return False
    for i in range(3, int(math.sqrt(n)) + 1, 2):
        if n % i == 0:
            return False
    return True


def next_prime(n):
    if n % 2 == 0:
        n += 1
    else:
        n += 2
    while not is_prime(n):
        n += 2
    return n


a = next_prime(1000000)
while not is_prime(sum_digits(a)):
    a = next_prime(a)
b = next_prime(a)
while not is_prime(sum_digits(b)):
    b = next_prime(b)
print(str(a) + str(b))