#include<iostream>
#include<atcoder/modint>
using namespace std;
using mint=atcoder::modint998244353;
int N,M;
main()
{
	cin>>N>>M;
	int i=1;
	mint ans=0;
	while(i<=M)
	{
		int f=N/i;
		int r=f==0?M+1:N/f+1;
		if(r>M)r=M+1;
		mint mf=f;
		mint mr=r,mi=i;
		mint ms=mr*(mr-1)/2-mi*(mi-1)/2;
		ans+=(mf+mf*(mf+1)/2)*ms;
		i=r;
	}
	cout<<ans.val()<<endl;
}