use proconio::input;

const MD: i64 = 998244353;
const HALF: i64 = MD / 2 + 1;

fn solve(n: usize, m: usize) -> i64 {
  let mu = mu(n.max(m));
  let mut ans = 0;
  for d in 1..=n.max(m) {
    let a = (n / d) as i64;
    let b = (m / d) as i64;
    let mut x = (MD + mu[d] as i64) * d as i64 % MD * d as i64;
    x %= MD;
    x *= a * (a + 1) % MD * HALF % MD;
    x %= MD;
    x *= b * (b + 1) % MD * HALF % MD;
    ans += x;
    ans %= MD;
  }
  ans
}

fn mu(n: usize) -> Vec<i8> {
  let mut t = vec![1; n + 1];
  t[0] = 0;
  let mut p = vec![true; n + 1];
  p[0] = false;
  p[1] = false;
  for k in 2..=n {
    if p[k] {
      for i in 1.. {
        let ki = k.saturating_mul(i);
        if ki > n {
          break;
        }
        p[ki] = false;
        t[ki] *= -1;
        let kki = ki.saturating_mul(k);
        if kki > n {
          continue;
        }
        t[kki] = 0;
      }
    }
  }
  t
}

fn main() {
  input! {
    n: usize,
    m: usize,
  }
  let ans = solve(n, m);
  println!("{}", ans);
}

#[cfg(test)]
mod tests {
  use num::Integer;
  use crate::{solve, MD};

  #[test]
  fn test() {
    for n in 1..=3000 {
      for m in 1..=3000 {
        let ans = solve(n, m);
        let ans_naive = {
          let mut ans = 0;
          for i in 1..=n {
            for j in 1..=m {
              if i.gcd(&j) == 1 {
                ans += (i * j) as i64;
                ans %= MD;
              }
            }
          }
          ans
        };
        if ans != ans_naive {
          panic!("! {} {} -> {} {}", n, m, ans, ans_naive);
        }
      }
    }
  }

  #[test]
  fn test_sample() {
    assert_eq!(solve(3, 5), 69);
    assert_eq!(solve(31, 13), 29391);
    assert_eq!(solve(10000000, 10000000), 283556728);
  }
  
  #[test]
  fn test_case() {
    assert_eq!(solve(21, 2940), 605156436);
  }
}