(q,),*e=[[*map(int,s.split())]for s in open(0)]
M=998244353
N=2*10**6
F=[1]*N;l,f=F[:],F[:]
for i in range(2,N):F[i]=F[i-1]*i%M;l[i]=-(M//i)*l[M%i]%M;f[i]=f[i-1]*l[i]%M
c=lambda l,k:(k<=l)*F[l]*f[k]*f[l-k]%M
def pf(n):
 a,f=[],2
 while f*f<=n:
  if n%f:f+=1
  else:a+=[f];n//=f
 if n>1:a+=[n]
 return a
t=0
for a,b in e:
  l=len(pf(a))
  t+=l
  print(c(t-1,b-1))