import java.io.BufferedReader;
import java.io.InputStreamReader;

public class Main {
	public static void main(String[] args) throws Exception {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		long n = Long.parseLong(br.readLine());
		br.close();

		if (n > 1200000) {
			return;
		}

		int mod = 998244353;
		long ans = 0;
		for (long i = 1; i <= n; i++) {
			long v1 = n / i;
			long v2 = v1 * (v1 + 1) / 2;
			long v3 = v2 * i;

			long v4 = n % i;
			long v5 = (i - 1 - v4) * v1;
			ans += v3 - v5;
			ans %= mod;
		}
		System.out.println(ans);
	}
}