A three-digit number, each digit is a, b, c, they are not equal to each other, and they are not zero, a, b, c can be used to arrange a total of six different three-digit numbers, if the sum of these six numbers It is 2664, so what is the largest number in this number?
一个三位数，各位数字分别为a、b、c，它们互不相等，且都不为零，用a、b、c共可排得六个不同三位数，如果这六个数的和是2664，那么这个数中最大的数是多少．
<result>921</result>