202
202 is the natural number following 201 and preceding 203.[1] In base-10 notation, it is an even composite number and a semiprime, expressed as the product of the distinct primes 2 and 101, with positive divisors 1, 2, 101, and 202.[2][1] It qualifies as a Smith number, where the sum of its digits (2 + 0 + 2 = 4) equals the sum of the digits in its prime factors (2 + 1 + 0 + 1 = 4).[3][4] Additionally, 202 is strobogrammatic, meaning its representation remains unchanged when rotated 180 degrees, due to the rotational symmetry of its digits.[5] A distinctive property is that its cube, 202³ = 8,242,408, consists exclusively of even digits (0, 2, 4, 6, 8).[6]Calendar and Chronology
Julian Calendar Details
The Julian calendar, introduced by Julius Caesar in 45 BC following reforms advised by the Alexandrian astronomer Sosigenes, replaced the irregular Roman republican calendar with a solar system averaging 365.25 days per year to better align with the seasons.[7] It fixed the year at 365 days in common years, with a leap day added every fourth year by repeating the 24th day before the Kalends of March (effectively inserting February 29), without exceptions for century years.[7] This structure yielded a year length of 365 days and 6 hours, slightly longer than the tropical year of approximately 365.2422 days, causing a gradual drift of about 1 day every 128 years.[8] For 202 AD, a common year since 202 is not divisible by 4, the calendar spanned 365 days from January 1 to December 31, with February having 28 days and no intercalary adjustment.[7] The 12 months retained names derived from Roman tradition, with lengths adjusted from the pre-Julian calendar by redistributing 10 or 11 days to shorter months while preserving the 31-day lengths of January, April, June, September? No, standard: the reform added days to achieve the fixed pattern, leaving January, April? Wait, actually: the Julian months were set as follows, unchanged in long months from late republican adjustments:| Month | Days (common year) |
|---|---|
| January | 31 |
| February | 28 |
| March | 31 |
| April | 30 |
| May | 31 |
| June | 30 |
| July | 31 |
| August | 31 |
| September | 30 |
| October | 31 |
| November | 30 |
| December | 31 |