vampire number

English

Examples

1260 = 21 × 60
1395 = 15 × 93
102510 = 201 × 510
104260 = 260 × 401

Noun

vampire number (plural vampire numbers)

  1. (mathematics) A composite natural number with an even number of digits that can be factored into two natural numbers (called "fangs") each with half as many digits as the original number, and where the two factors contain precisely all the digits of the original number, in any order, counting multiplicity.