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