If you were to read tomorrow's newspaper it is intuitively more likely that the whole number 1 would appear more times than 643689443. Is there an expected distribution of numbers used in general?
I'm not sure how to express this in mathematical terms.
Your intuition is correct. Take a look at Benford's Law.
It only applies to the first digit in a number. But, as mentioned in the article, there are generalizations to longer strings.