| Digital Divisibility Tests: From Carlos Rivera's Prime Puzzles and Problems collection. Carlos asks for the general divisibility rules for any prime number. |
| Divisibility Criteria: Ways of telling whether one number divides another without actually carrying the division through, constructed here in terms of the digits of the number. |
| Divisibility Tests: Jim Loy explains the divisibility rules up to 11, including a detailed study of 7. |
| Divisibility Tests: From the NRICH Maths Project Cambridge, England. Dr. Tim Rowland explains the smaller rules and looks at the rules to 7, 11, 13, and 19. |
| Divisibility Tests: From the Furman University Electronic Journal of Undergraduate Mathematics. Apoorva Khare's paper is available as an abstract, DVI, and PostScript. |
| Divisibility War: A card game to teach divisibility rules. |
| Explaining the Divisibility Rules: Proof of the elementary division rules, plus some lesser-known rules for larger divisors and other bases. |
| The Anti-Divisor: Introduction to unbiased non-divisor and using it in mathematical proofs. |
Classical
