Divisor 24281

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

The "Warren Oates Test" for Divisibility by 24281

To determine if any number is divisible by 24281, apply the "Warren Oates Test":

  1. If your number ("X") has 6 digits or more, separate the last (smallest) 5 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 6 digits, L = 0 and therefore R = X.
  2. Multiply L by 2876 and add to R.
  3. Take that result and cross off its final digit (units). Take this new number and subtract 2428 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 24281. That is, your original number is divisible by 24281 if (and only if) Y is. Now that it's much smaller, with basic knowledge of your 24281-times tables, it should be easy to visually see if Y is divisible by 24281. If the Y is still much larger than 24281, the above process can be repeated until it does reduce to within small multiples of 24281.

Easy!