import sys
input = sys.stdin.readline
MOD = 998244353
N = int(input())
if N>10**7:
    exit()
ans = 0
for i in range(1, N+1):
    cnt = N-(i-1)
    s = cnt//i
    a = cnt%i
    ans += i*(1+s)*s//2 + a*(s+1)
    ans %= MOD
print(ans)