Year
Astronomical years
An average Gregorian year is 365.2425 days (52.1775 weeks, 8765.82 hours, 525949.2 minutes or 31556952 seconds). For this calendar, a common year is 365 days (8760 hours, 525600 minutes or 31536000 seconds), and a leap year is 366 days (8784 hours, 527040 minutes or 31622400 seconds). The 400-year cycle of the Gregorian calendar has 146097 days and hence exactly 20871 weeks.
Year-57