import sys
readline=sys.stdin.readline

def Inverse_Proportion(N):
    retu=[]
    for i in range(1,N+1):
        if i==N or N//i>N//(i+1):
            retu.append(((i,i+1),N//i))
        else:
            for j in range(N//i,0,-1):
                retu.append(((N//(j+1)+1,N//j+1),j))
            break
    return retu

N,M=map(int,readline().split())
mod=998244353
ans=0
for (l,r),j in Inverse_Proportion(N):
    l=min(l,M+1)
    r=min(r,M+1)
    ans+=(l+r-1)*(r-l)//2*j*(j+1)//2+(l+r-1)*(r-l)//2*j
    ans%=mod
print(ans)