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
| 6PM to 3PM | 9AM to 10AM | 3PM to 12PM |
| 11PM to 7PM | 5PM to 8AM | 12AM to 11PM |
| 4AM to 10AM | 2AM to 4AM | 10AM to 1PM |
| 4AM to 9AM | 6PM to 6AM | 2AM to 8AM |
| 9PM to 5AM | 7AM to 4PM | 10PM to 10AM |
| 7PM to 10PM | 10AM to 6AM | 4PM to 4AM |
