from collections import defaultdict
def prime_factorization(w,d):
    cnt = 2
    while w > 1:
        if cnt > int(w ** (1/2)):
            d[w] += 1
            break
        while w % cnt == 0:
            d[cnt] += 1
            w //= cnt
        cnt += 1
d = defaultdict(int)
n = int(input())
prime_factorization(n,d)
ans = 0
for key in d.keys():
    ans += key * d[key]
print(ans)