use ac_library::ModInt998244353;
use proconio::input;

type Mint = ModInt998244353;

fn main() {
    input! {
        n: usize, m: usize
    }

    let f = |d: usize, n: usize| {
        let k = n / d;
        Mint::from(k * (k + 1) / 2) * d
    };

    let (n, m) = (n.min(m), n.max(m));
    let mut ans = f(1, n) * f(1, m);
    let mut mu = vec![2i8; n + 1];
    for i in 2..=n {
        if mu[i] == 2 {
            for j in (i..=n).step_by(i) {
                mu[j] = match mu[j] {
                    1 | 2 => -1,
                    -1 => 1,
                    0 => 0,
                    _ => unreachable!(),
                }
            }
            for j in (i * i..=n).step_by(i * i) {
                mu[j] = 0;
            }
        }

        if mu[i] == 1 {
            ans += f(i, n) * f(i, m);
        } else if mu[i] == -1 {
            ans -= f(i, n) * f(i, m);
        }
    }
    println!("{ans}");
}

// sum mu(d)*ab for a<=n, b<=m, d|a, d|b