MathDB
Game with divisors, gcd and lcm

Source: Kvant Magazine No. 2 2023 M2737

April 19, 2023
number theorycombinatorics

Problem Statement

All the divisors of a) 8ā‹…1068\cdot 10^6 and b) 36010360^{10} are written on a board. At a move, we can take two numbers, neither of which is divisible by the other, and replace them with their greatest common divisor and lowest common multiple. At some point, we will no longer be able to perform new operations. How many different numbers will be on the board at this moment?
Proposed by V. Bragin