import sys

X,A,Y,B = list(map(int,input().split()))

x_prime = [0] * (10 ** 6 + 1)
y_prime = [0] * (10 ** 6 + 1)
i = 2
while i ** 2 <= X:
    if X % i == 0:
        x_prime[i] += 1
        X = X // i
    else:
        i += 1
x_prime[X] += 1
i = 2
while i ** 2 <= Y:
    if Y % i == 0:
        y_prime[i] += 1
        Y = Y // i
    else:
        i += 1
y_prime[Y] += 1
for i in range(2,10 ** 6 + 1):
    if x_prime[i] * A < y_prime[i] * B:
        print('No')
        exit()
print('Yes')