use proconio::input;
use ac_library::ModInt998244353 as Mint;

fn main(){
    input!{
        n: i64,
    }
    assert!(n <= 1200000);

    let mut ans = Mint::new(0);
    for j in 1..=n{
        let m = n/j;
        let s = m*(m-1)/2;
        let mut now = Mint::new(j)*Mint::new(s);
        now += Mint::new(m)*Mint::new(n-m*j+1);
        ans += now;
    }

    println!("{}", ans.val());
}