## https://yukicoder.me/problems/no/2940


MOD = 998244353

def main():
    N = int(input())

    inv2 = pow(2, MOD - 2, MOD)
    answer = 0
    for j in range(1, N + 1):
        n = N // j

        n_tot = (n * (n - 1)) % MOD
        n_tot *= inv2
        n_tot %= MOD

        x = (n + (j * n_tot) % MOD) % MOD

        m = N % j
        x += (n * m) % MOD
        x %= MOD

        answer += x
        answer %= MOD
    
    print(answer)














if __name__ == "__main__":
    main()