There are many four-digit positive integers in which the product of the digits is equal to 5!. What is the sum of the largest and smallest such four-digit numbers?
The smallest is: 1,358 =1 + 3 + 5 + 8 = 17 The largest is: 8,531 = 8 + 5 + 3 + 1 = 17 Note: it is the same number reversed. if you wish a different number, then 6,541 would be the next largest such number.