n=int(eval(input()))

from itertools import *

s=[*accumulate(list(range(n+1)))]

print((sum(i*s[n//i] for i in range(1,n+1))))
n=int(eval(input()))

print((sum(n//i*(n//i+1)*i//2 for i in range(1,n+1))))
n = int(eval(input()))
from itertools import *

s = [*accumulate(list(range(n + 1)))]
print((sum(i * s[n // i] for i in range(1, n + 1))))

n = int(eval(input()))
print((sum(n // i * (n // i + 1) * i // 2 for i in range(1, n + 1))))

-from itertools import * - -s = [*accumulate(list(range(n + 1)))] -print((sum(i * s[n // i] for i in range(1, n + 1)))) +print((sum(n // i * (n // i + 1) * i // 2 for i in range(1, n + 1))))