n,m=map(int,input().split())
a=0
b=998244353
s=0
def c(x):
  s=(min(m+1,n//(x+1)+1)+min(m,n//x))*(min(m,n//x)-min(m,n//(x+1)))*499122177
  s%=b
  return (s*x*(x+3)*499122177)%b
for x in range(1,int(n**.5)+1):
  a+=c(x)
  a%=b
  if n//x!=x :
    a+=clac(n//x)
    a%=b
print(a)