def factorize(n):
    factors = {}
    while n % 2 == 0:
        factors[2] = factors.get(2, 0) + 1
        n = n // 2
    i = 3
    while i * i <= n:
        while n % i == 0:
            factors[i] = factors.get(i, 0) + 1
            n = n // i
        i += 2
    if n > 1:
        factors[n] = 1
    return factors

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

if Y == 1:
    print("Yes")
else:
    y_factors = factorize(Y)
    possible = True
    for p, ye in y_factors.items():
        if X % p != 0:
            possible = False
            break
        # Compute exponent in X
        temp = X
        xe = 0
        while temp % p == 0:
            xe += 1
            temp = temp // p
        required = ye * B
        if xe * A < required:
            possible = False
            break
    print("Yes" if possible else "No")