Divisor 24793

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

The "ebren durling Test" for Divisibility by 24793

To determine if any number is divisible by 24793, apply the "ebren durling 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 828 and add to R.
  3. Take that result and cross off its final digit (units). Take this new number and add 7438 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 24793. That is, your original number is divisible by 24793 if (and only if) Y is. Now that it's much smaller, with basic knowledge of your 24793-times tables, it should be easy to visually see if Y is divisible by 24793. If the Y is still much larger than 24793, the above process can be repeated until it does reduce to within small multiples of 24793.

Easy!