from collections import Counter

def prime_factorize(n):
    a = []
    while n % 2 == 0:
        a.append(2)
        n //= 2
    f = 3
    while f * f <= n:
        while n % f == 0:
            a.append(f)
            n //= f
        else:
            f += 2
    if n != 1:
        a.append(n)
    return a

x, a, y, b = map(int, input().split())
cx = Counter(prime_factorize(x))
cy = Counter(prime_factorize(y))
for k, v in cy.items():
    if v * b > cx[k] * a:
        print('No')
        break
else:
    print('Yes')