import sys
from math import gcd
sys.setrecursionlimit(10**7)
def I(): return int(sys.stdin.readline().rstrip())
def MI(): return map(int,sys.stdin.readline().rstrip().split())
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))
def LI2(): return list(map(int,sys.stdin.readline().rstrip()))
def S(): return sys.stdin.readline().rstrip()
def LS(): return list(sys.stdin.readline().rstrip().split())
def LS2(): return list(sys.stdin.readline().rstrip())


def divisor(n):  # nの約数全列挙
    res = []
    for i in range(1,int(n**.5)+1):
        if n % i == 0:
            res.append(i)
            if i != n//i:
                res.append(n//i)
    return res


N = I()
div = divisor(gcd(N,N*(N+1)//2))
print(sum(div))