9*9*9 = 729 ways.
It is -987. The smallest positive 3-digit integer with unique digits is 102.
A number divisible by 123456789 must be 0 or bigger than 123456789. It must, therefore have 1 digit or 9 digits (or more). A remainder of 1 makes no difference to the number of digits. In any case, there can be no number of 4 digits that is divisible by 123456789.
There are 7,290 different 4-digit numbers that can be formed from the digits 1-9 without repetition.
81
There are 3024 of them.
The answer is 9*9!/9*109 = 0.0003629 approx.
The answer is a negative or positive integer with one or two digits.
There are 60480 numbers.
12
The least possible integer is -98765432. The least possible positive integer is 10234567.
First, separate the negative and positive integers (put them into two separate groups). If there is a zero, you can put it in its own group - or put it into the same group with the positive integers. Negative integers come first, then zero, then positive integers.For positive integers:An integer with less digits comes before an integer with more digits.For integers with the same number of digits, look at the first digit. The integer with the smaller digit in this position comes first.If the first digit is the same, look at the second digit. If those are equal, look at the third digit, etc.For negative integers, it is the other way round - for example, an integer with MORE digits comes first.
-123456787