Do I really need to write out the value on a check?

Not true, I’m going to change it from 14/100 to 14000000000000/100. I’ll be rich!

Back in college for one year the parking/bus pass was $121 a year and I had to mail in a check. The first quarter instead of writing out the amount I wrote “eleven squared” (my rebellion threshold was low back then). It cleared without issue so I did it the next two quarters.

That line is notionally called a “negamegalinium”.

As has been noted, under UCC 3 the written amount will be dispositive in the event of a dispute.