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