The number 204 is unprimeable because no single digit can be changed to make it prime. In contrast, the number 207 is not unprimeable because changing the first digit to 0, 1, 3, 6, or 9 or the second digit to 2, 5, or 7 would make it prime.
Write a function to determine whether the input number is unprimeable.

Solution Stats

35 Solutions

17 Solvers

Last Solution submitted on May 25, 2026

Last 200 Solutions

Problem Comments

Solution Comments

Show comments
Loading...