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