Problem Archive

We call a positive integer double pandigital if it uses all the digits $0$ to $9$ exactly twice (with no leading zero). For example, $40561817703823564929$ is one such number.

How many double pandigital numbers are divisible by $11$?

Solution
No solution yet. Write yours at solutions/s491.md.
Problems sourced from Project Euler · Non-commercial & educational use only · CC BY-NC-SA 4.0