There is a class of three-digit numbers, the product of the digits in each digit is 18, among all such three-digit numbers, what is the difference between the largest number and the smallest number?
有一类三位数，各数位上的数字之积是18，在所有这样的三位数中，最大的数与最小的数的差是多少？
<gadget id="calculator">921 - 129</gadget>
<output>792</output>

<result>792</result>