Divisor 7577

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

The "Tennyson Taylor Bardwell Test" for Divisibility by 7577

To determine if any number is divisible by 7577, apply the "Tennyson Taylor Bardwell 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 164 and subtract this from R.
  3. Take that result and cross off its final digit (units). Take this new number and subtract 2273 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 7577. That is, your original number is divisible by 7577 if (and only if) Y is. Now that it's much smaller, with basic knowledge of your 7577-times tables, it should be easy to visually see if Y is divisible by 7577. If the Y is still much larger than 7577, the above process can be repeated until it does reduce to within small multiples of 7577.

Easy!