sum_of_prime_multiples

def is_prime(num):
    if num <= 1:
        return False
    for i in range(2, int(num ** 0.5) + 1):
        if num % i == 0:
            return False
    return True

def prime_factors_sum(n):
    if is_prime(n):
        return n

    factors = []
    divisor = 2
    while n > 1:
        while n % divisor == 0:
            factors.append(divisor)
            n //= divisor
        divisor += 1

    return sum(factors)

# Input from the user
num = int(input("Enter a natural number: "))
result = prime_factors_sum(num)
print("Output:", result)