I am a 3 digit #. All 3 digits are the same . I could not be any greater . What # am I ?

To find the answer to this question, we need to consider the given clues.

First, we know that the number is a three-digit number where all three digits are the same. This means that the number is a repetition of a single digit.

Second, we are told that the number could not be any greater. This implies that the number is already at its maximum value.

Since all three digits are the same, the maximum value for a three-digit number where all digits are the same is 999.

Therefore, the answer is 999.