refactor: Enhance docs, code, add tests in HarshadNumber (#6745)
#6988
| Job | Run time |
|---|---|
| 42s | |
| 3m 20s | |
| 4m 2s |
HarshadNumber (#6745)
#6988
| Job | Run time |
|---|---|
| 42s | |
| 3m 20s | |
| 4m 2s |