from itertools import permutations

def calculate_product(item):
    x = (len(item) // 2) + (len(item) % 2)
    return int(''.join(item[0:1])) * int(''.join(item[1:x]))

def main():
    max_number = int(input("Enter the maximum number: "))
    number = [str(x) for x in range(1, max_number + 1)]
    p_numbers = permutations(number)
    unique_products = set()

    for item in p_numbers:
        product = calculate_product(item)
        if product == int(''.join(item[x:])) and len(item) > 1:
            unique_products.add(int(''.join(item[x:])))

    print(sum(unique_products))

if __name__ == "__main__":
    main()