Week
Symbol: W
The time unit week is equal to 7 days = 168 hours = 10,080 minutes = 604,800 seconds.
The week is not an SI unit.
Combining seven days to a unit of one week results of the length of one month (moon), which lasts just a bit more than 28 days. The four phases of the moon (new moon, half moon increasing, full moon, half moon decreasing) suggests to devide 28 days of a month into four weeks per seven days.
1s = 0.00000165344W