The biggest 4 digit number that can be made from using the digits of 850236, using a digit at most once, is 8653.
210
If the numbers are not repeated then the highest 5 digit even number to be made out of 0123456789 is : 98764.
The first digit can by selectd in one of two ways, since a number starting with zero would not be a 5-digit number. After that, each of the other four digits can be selected in 3 ways. So the number of 5-digit numbers is 2*34 = 162
5040 numbers can be made.
120 5-digit numbers can be made with the numbers 12345.
In decimal, a digit is one of the ten symbols that represent the numbers 0 to 9. A number can be made up of one or more digits. For example: 1 is a digit (as well as a number of course). 11 is a number made up of 2 digits.
59
6*7*7 = 294
6
9
No, it is not the biggest. There is no biggest. Indeed, there is a part of mathematics which deals with transfinite numbers: these are different orders of infinity!