x,a,y,b = map(int,input().split())
if x==1:
	if y==1: print('Yes')
	else: print('No')
	exit()
if y==1:
	print('Yes')
	exit()
n = x
rep = int(n**0.5)+1
plist = dict()
for i in range(2,rep):
	c = 0
	while n%i==0:
		n //= i
		c += 1
	plist[i] = c
	if n==1: break
if n!=1:
	plist[n] = 1
ok = True
n = y
rep = int(n**0.5)+1
for i in range(2,rep):
	c = 0
	while n%i==0:
		n //= i
		c += 1
	if c>0:
		if plist.get(i) is None:
			ok = False; break
		if plist[i]*a<c*b:
			ok = False; break
if n!=1:
	if plist.get(n) is None:
		ok = False
	elif plist[n]*a<b:
		ok = False
if ok: print('Yes')
else: print('No')