题解 | #完全数计算#

def find_perfect_num(num):
    sum_num = []

    for i in range(1, num):
        if num % i == 0:
            sum_num.append(i)
    if sum(sum_num) == num:
        return True
    return False


n = int(input())
find_perfect = []
for i in range(1, n + 1):
    if find_perfect_num(i):   # 表示i 满足上述函数的要求
        find_perfect.append(i)


print(len(find_perfect))