Divisor 7459

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

The "AJF Test" for Divisibility by 7459

To determine if any number is divisible by 7459, apply the "AJF Test":

  1. If your number ("X") has 7 digits or more, separate the last (smallest) 6 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 7 digits, L = 0 and therefore R = X.
  2. Multiply L by 494 and add to R.
  3. Take that result and cross off its final digit (units). Take this new number and add 746 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 7459. That is, your original number is divisible by 7459 if (and only if) Y is. Now that it's much smaller, with basic knowledge of your 7459-times tables, it should be easy to visually see if Y is divisible by 7459. If the Y is still much larger than 7459, the above process can be repeated until it does reduce to within small multiples of 7459.

Easy!