require'prime'
n,k=gets.split.map &:to_i
r=t=0
o=Hash[n.prime_division]
(2...n).map{|i|
	q=i.prime_division
	l=s=1
	q.each{|n,p|l+=[o[n].to_i,p].min;s*=p+1}
	(l>k&&r<s)&&(r=s;t=i)
}
p t