1,272. The Length of Months and Years

Hilchos Kiddush HaChodesh 6:4

A lunar year includes 12 months as described in halacha 6:3, totaling 354 days, eight hours and 876 chalakim. A leap year of 13 lunar months equals 383 days, 21 hours and 589 chalakim. A solar year is 365 days and six hours, exceeding a lunar year by ten days, 21 hours and 204 chalakim.

Hilchos Kiddush HaChodesh 6:5

When the days of a lunar month are divided into groups of seven, corresponding to weeks, there remains one day, 12 hours and 793 chalakim. This is called the remainder of a lunar month and it is abbreviated at “1, 12, 793.” When the days of a lunar year are divided into groups of seven, corresponding to weeks, there remains four days, eight hours and 876 chalakim. This is called the remainder of a regular lunar year and is abbreviated as “4, 8, 876.” The remainder of a leap year is five days, 21 hours and 589 chalakim, abbreviated as “5, 21, 589.”