prime numbers and wordle

 What fun ways do you have of determining if a number is prime? And what does this have to do with wordle?

Not much, except that we recently got to wordle number 1000 and then 1001 and then 1002 and today it's number 1003, so I find myself wondering which of those numbers are prime?

1001 could be prime. It sure looks prime. And 1003 looks like it could be prime as well.

In what year was 1001 first factored? Yes, it has factors. It's not prime. Here's my favorite reason:

1001 is of the form a^3 + 1 , and a^3 + 1 is never prime because it is divisible by a +1. For 1001, a is 10, and therefore 1001 is divisible by 11.

Can we find just as fun a reason for explaining why 1003 is not prime?