Verified Answer :

\(5\)x\(81 = 405\)

This is how I found it:
Divide \(405\) to any number
In this case I divided \(405\) to \(5\) and got \(81\)
That means \(5\)x\(81 = 405\)
Hope this helped you =)

1 times 405 equals 405

3 times 135 equals 405

5 times 81 equals 405

9 times 45 equals 405

15 times 27 equals 405

27 times 15 equals 405

45 times 9 equals 405

81 times 5 equals 405

135 times 3 equals 405

405 times 1 equals 405