In standard English, none of the spelled out numbers from one to nine hundred ninety nine contains the letter A. The first time a appears is in one thousand.
This works because the basic number words avoid that letter. Words like one, two, three, four, five, six, seven, eight, nine, ten, eleven, twelve, thirteen, twenty, thirty, forty, fifty, sixty, seventy, eighty, ninety, hundred, and combinations made from them, all contain other vowels but not a.
For example:
- forty two has no a
- one hundred sixteen has no a
- nine hundred ninety nine still has no a
The pattern breaks at one thousand, because thousand includes the letter a. After that, many larger numbers also include it for the same reason.
This fact is a fun reminder that language patterns are not always obvious. It feels surprising because there are so many numbers before 1000, yet English manages to avoid one very common letter all the way through them.
