0 (zero is a digit), but if you want a nonzero number, then 1, or if you're counting negatives as 'smaller' than positives (they are less than, not really smaller, though), then -9 would be it.
Take the smallest 6-digit even number, then subtract one from it.
One
The smallest three digit number is 0.01. One less than that would be -1.01.
1111
1
The smallest negative one digit number is -9, and the smallest positive one digit number is either 0 or 1, I'm not sure about the positive.
-8
-99 is the smallest two digit number.-99 is the smallest two digit number.-99 is the smallest two digit number.-99 is the smallest two digit number.
Take the smallest 6-digit even number, then subtract one from it.
One
-9
The smallest three digit number is 0.01. One less than that would be -1.01.
The smallest odd positive number is 1 (one).
105 - is the smallest tree-digit number that has the digit 5
1111
1
10,000,000 is the smallest 8 digit number 99,999,999 is the largest 8 digit number