Divisor 23041

Prime Number:
Yes!
Divisibility test:
The "ehemmete Test"
Test Discovered by:
Matt Parker
Date:
11/11/2024

The "ehemmete Test" for Divisibility by 23041

To determine if any number is divisible by 23041, apply the "ehemmete Test":

  1. If your number ("X") has 8 digits or more, separate the last (smallest) 7 digits from the rest. This makes two smaller numbers, call them Left and Right (note: don't add in trailing zeros to L). If there are fewer than 8 digits, L = 0 and therefore R = X.
  2. Multiply L by 206 and add to R.
  3. Take that result and cross off its final digit (units). Take this new number and subtract 2304 times the digit you just crossed off. Call this final result "Y".
  4. Y will be much smaller than X, but we have preserved divisibility by 23041. That is, your original number is divisible by 23041 if (and only if) Y is. Now that it's much smaller, with basic knowledge of your 23041-times tables, it should be easy to visually see if Y is divisible by 23041. If the Y is still much larger than 23041, the above process can be repeated until it does reduce to within small multiples of 23041.

Easy!