All the gummy machines at a candy factory work at the same rate. Six machines working simultaneously can complete a big order in 22 hours. How many hours would it take to fill the order if the number of working machines decreased by a factor of 2?
If six machines working simultaneously can complete a big order in 22 hours, then 1 machine takes 6 * 22 = <<6*22=132>>132 hours to complete the same order.
If the number of working machines decreased by a factor of 2, then the number of machines becomes 6/2 = <<6/2=3>>3 machines.
Therefore, it would take 3 * 132 = <<3*132=396>>396 hours to fill the order if the number of working machines decreased by a factor of 2. Answer: \boxed{396}.