def main():
    n = int(input())
    if n == 1:
        print(0)
        return
    ans = 0
    a = prime_factors(n)
    for i in range(len(a)):
        ans += a[i]
    print(ans)
def prime_factors(n):
    i = 2
    factors = []
    while i * i <= n:
        if n % i:
            i += 1
        else:
            n //= i
            factors.append(i)
    if n > 1:
        factors.append(n)
    return factors
main()