//GIVE ME AC!!!!!!!!!!!!!!!!!
#pragma GCC target("avx")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include<bits/stdc++.h>
#define ll long long
using namespace std;
const ll mod=998244353;
int64_t read_int() {
    int64_t ret = 0, sgn = 1;
    int ch = getchar_unlocked();
    while (isspace(ch)) { ch = getchar_unlocked(); }
    if (ch == '-') { sgn = -1; ch = getchar_unlocked(); }
    for (; isdigit(ch); ch = getchar_unlocked())
        ret = (ret * 10) + (ch - '0');
    ungetc(ch, stdin);
    return sgn * ret;
}
int main(){
  ll n=read_int(),m=read_int();
  ll ans=0;
  for(ll i=1;i<=m;i++){
    ans+=n/i*i+(n/i)*(n/i+1)/2*i;
    ans%=mod;
  }
  cout<<ans<<endl;
}