from collections import defaultdict

def prime_factorize(number):
    primes = defaultdict(int)
    while number % 2 == 0:
        primes[2] += 1
        number //= 2
    for p in range(3, int(number**0.5)+1, 2):
        while number % p == 0:
            primes[p] += 1
            number //= p
    if number != 1:
        primes[number] += 1
    return primes

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

X_factors = prime_factorize(X)
Y_factors = prime_factorize(Y)

for key, value in Y_factors.items():
    values = value * B
    if X_factors[key]*A < values:
        print("No")
        exit()
print("Yes")