There are total 21 hours or 1260 minutes from 4am to 1am. In words, this duration is equal to twenty-one hours or one thousand two hundred sixty minutes.
How many hours from
| 12PM to 9AM | 11AM to 8AM | 11PM to 11AM |
| 6PM to 6AM | 5AM to 12PM | 5PM to 1PM |
| 7AM to 3PM | 2PM to 12PM | 9PM to 1AM |
| 3AM to 4PM | 10AM to 1PM | 4AM to 12AM |
| 5AM to 10AM | 5AM to 1AM | 8AM to 11AM |
| 12PM to 2PM | 6PM to 9PM | 8AM to 4AM |
