N = int(eval(input()))

l = list(range(1, N+1))





def calc(i):

    return sum(list(range(i, N+1, i)))





ans = 0

for i in range(1, N+1):

    ans += calc(i)



print(ans)
N = int(eval(input()))

l = list(range(1, N+1))





def calc(i):

    return (i + N//i * i) * (N//i) // 2





ans = 0

for i in range(1, N+1):

    ans += calc(i)



print(ans)
N = int(eval(input()))
l = list(range(1, N + 1))


def calc(i):
    return sum(list(range(i, N + 1, i)))


ans = 0
for i in range(1, N + 1):
    ans += calc(i)
print(ans)

N = int(eval(input()))
l = list(range(1, N + 1))


def calc(i):
    return (i + N // i * i) * (N // i) // 2


ans = 0
for i in range(1, N + 1):
    ans += calc(i)
print(ans)

-    return sum(list(range(i, N + 1, i))) +    return (i + N // i * i) * (N // i) // 2