97531
9,999,876 is the greatest seven-digit number using four different digits.
1324
987654
The greatest 9-digit number using three different digits is 999888777, formed by using the digits 9, 8, and 7 in descending order. The smallest 9-digit number using three different digits is 100000000, created with the digits 1, 0, and 0. This arrangement ensures that the number starts with 1, followed by the zeros to maintain the smallest value.
7,543
9,999,876 is the greatest seven-digit number using four different digits.
1324
987654
The greatest 9-digit number using three different digits is 999888777, formed by using the digits 9, 8, and 7 in descending order. The smallest 9-digit number using three different digits is 100000000, created with the digits 1, 0, and 0. This arrangement ensures that the number starts with 1, followed by the zeros to maintain the smallest value.
To be an even number then the final digit = 2. The largest single prime digit is 7 (as both 8 and 9 are composite). The greatest even number fulfilling the conditions is 77777772.
7,543
Proceed from left to right, using the largest possible digit in each position.
1080, 9989
smallest=1234 greatest=4321
9542
.961
987,654,321