#include <bits/stdc++.h>

using i64 = long long;
template<class T>
constexpr T power(T a, i64 b) {
    T res {1};
    for (; b; b /= 2, a *= a) {
        if (b % 2) {
            res *= a;
        }
    }
    return res;
}

constexpr i64 mul(i64 a, i64 b, i64 p) {
    i64 res = a * b - i64(1.L * a * b / p) * p;
    res %= p;
    if (res < 0) {
        res += p;
    }
    return res;
}

template<i64 P>
struct MInt {
    i64 x;
    constexpr MInt() : x {0} {}
    constexpr MInt(i64 x) : x {norm(x % getMod())} {}
    
    static i64 Mod;
    constexpr static i64 getMod() {
        if (P > 0) {
            return P;
        } else {
            return Mod;
        }
    }
    constexpr static void setMod(i64 Mod_) {
        Mod = Mod_;
    }
    constexpr i64 norm(i64 x) const {
        if (x < 0) {
            x += getMod();
        }
        if (x >= getMod()) {
            x -= getMod();
        }
        return x;
    }
    constexpr i64 val() const {
        return x;
    }
    constexpr MInt operator-() const {
        MInt res;
        res.x = norm(getMod() - x);
        return res;
    }
    constexpr MInt inv() const {
        return power(*this, getMod() - 2);
    }
    constexpr MInt &operator*=(MInt rhs) & {
        if (getMod() < (1ULL << 31)) {
            x = x * rhs.x % int(getMod());
        } else {
            x = mul(x, rhs.x, getMod());
        }
        return *this;
    }
    constexpr MInt &operator+=(MInt rhs) & {
        x = norm(x + rhs.x);
        return *this;
    }
    constexpr MInt &operator-=(MInt rhs) & {
        x = norm(x - rhs.x);
        return *this;
    }
    constexpr MInt &operator/=(MInt rhs) & {
        return *this *= rhs.inv();
    }
    friend constexpr MInt operator*(MInt lhs, MInt rhs) {
        MInt res = lhs;
        res *= rhs;
        return res;
    }
    friend constexpr MInt operator+(MInt lhs, MInt rhs) {
        MInt res = lhs;
        res += rhs;
        return res;
    }
    friend constexpr MInt operator-(MInt lhs, MInt rhs) {
        MInt res = lhs;
        res -= rhs;
        return res;
    }
    friend constexpr MInt operator/(MInt lhs, MInt rhs) {
        MInt res = lhs;
        res /= rhs;
        return res;
    }
    friend constexpr std::istream &operator>>(std::istream &is, MInt &a) {
        i64 v;
        is >> v;
        a = MInt(v);
        return is;
    }
    friend constexpr std::ostream &operator<<(std::ostream &os, const MInt &a) {
        return os << a.val();
    }
    friend constexpr bool operator==(MInt lhs, MInt rhs) {
        return lhs.val() == rhs.val();
    }
    friend constexpr bool operator!=(MInt lhs, MInt rhs) {
        return lhs.val() != rhs.val();
    }
    friend constexpr bool operator<(MInt lhs, MInt rhs) {
        return lhs.val() < rhs.val();
    }
};

template<>
i64 MInt<0>::Mod = 998244353;

constexpr int P = 998244353;
using Z = MInt<P>;
std::vector<int> minp, primes;

void sieve(int n) {
    minp.assign(n + 1, 0);
    primes.clear();
    
    for (int i = 2; i <= n; i++) {
        if (minp[i] == 0) {
            minp[i] = i;
            primes.push_back(i);
        }
        
        for (auto p : primes) {
            if (i * p > n) {
                break;
            }
            minp[i * p] = p;
            if (p == minp[i]) {
                break;
            }
        }
    }
}

int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    
    i64 n;
    std::cin >> n;
    
    Z S1 = Z(n + 2) * (n - 1) / 2;
    Z S2 = Z(n) * (n + 1) * (2 * n + 1) / 6 - 1;
    
    std::vector<i64> v;
    for (i64 l = 1, r; l <= n; l = r + 1) {
        v.push_back(n / l);
        r = n / (n / l);
    }
    const i64 sqrtn = std::sqrt(n);
    sieve(sqrtn);
    
    std::vector<Z> f1(v.size()), f2(v.size());
    auto get = [&](auto &f, i64 x) -> Z & {
        if (x <= sqrtn) {
            return f[v.size() - x];
        } else {
            return f[n / x - 1];
        }
    };
    for (int i = 0; i < v.size(); i++) {
        Z x = v[i];
        f1[i] = x * (x + 1) / 2 - 1;
        f2[i] = x * (x + 1) * (2 * x + 1) / 6 - 1;
    }
    
    Z ps1 = 0, ps2 = 0;
    for (auto p : primes) {
        for (int i = 0; i < v.size(); i++) {
            if (1LL * p * p > v[i]) {
                break;
            }
            f1[i] -= Z(p) * (get(f1, v[i] / p) - ps1);
            f2[i] -= Z(p) * p * (get(f2, v[i] / p) - ps2);
        }
        ps1 += Z(p);
        ps2 += Z(p) * p;
    }
    
    S1 -= f1[0] - f1[1];
    S2 -= f2[0] - f2[1];
    Z ans = (S1 * S1 - S2) / 2;
    std::cout << ans << "\n";
    
    return 0;
}