def main():
  x, a, y, b = map(int, input().split())
  def factorization(n):
    arr = []
    tmp = n 
    m = int(-(-n**0.5//1))+1
    for i in range(2, m):
      if tmp % i == 0:
        cnt = 0
        while tmp % i == 0:
          cnt += 1
          tmp //= i
        arr.append([i, cnt])
    if tmp != 1:
      arr.append([tmp, 1])
    if len(arr) == 0:
      arr.append([n, 1])
    return arr
  X = factorization(x)
  Y = factorization(y)

  for i in range(len(Y)):
    yy = Y[i][0]
    for j in range(len(X)):
      if yy == X[j][0]:
        if Y[i][1]*b > X[j][1]*a:
          print('No')
          exit()
        else:
          break
    else:
      print('No')
      exit()
  print('Yes')
main()