Find the Number of Seven-Digit Numbers Which can be Formed with the Sum of the Digits Being Even

Answer: 1000000 is the smallest seven-digit number.

9999999- largest 7-digit.

As a result, there are 9000000 seven-digit numbers.

So the total number of seven-digit numbers is 9999999 – 1000000+1.

From 9000000 numbers, 4500000 have an even total of digits and the rest 4500000 have an odd amount of digits. Because every alternative number contains a total of even and odd digits.