#include <stdio.h>
#include <bits/stdc++.h>
#include <atcoder/all>
using namespace atcoder;
using mint = modint998244353;
using namespace std;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf 1000000001

mint sum(int n){
	mint ret = n;
	ret *= n+1;
	ret /= 2;
	return ret;
}

mint sum(int l,int r){
	mint ret = sum(r) - sum(l-1);
	return ret;
}

int main(){
	
	long long n,m;
	cin>>n>>m;
	mint ans = 0;
	for(long long i=1;i<=m;i++){
		long long ok = i,ng = m+1;
		while(ng-ok>1){
			long long mid = (ok+ng)/2;
			if(n/i == n/mid)ok = mid;
			else ng = mid;
		}
		//cout<<i<<','<<ok<<endl;
		long long x = n/i;
		ans += sum(1,x) * sum(i,ok);
		ans += sum(i,ok) * x;
		i = ok;
	}
	
	cout<<ans.val()<<endl;
	
    return 0;
}