from collections import defaultdict
def prime_list(x):
	i=2
	prime=defaultdict(int)
	while i*i<=x:
		while x%i==0:
			x//=i
			prime[i]+=1
		i+=1
	if x>1:
		prime[x]+=1
	return prime

x,a,y,b=map(int,input().split())
X=prime_list(x)
Y=prime_list(y)
ok=1
for key in Y:
	if Y[key]*b>X[key]*a:
		ok=0
		break
print("Yes" if ok else "No")