What is 28?

28 is a natural number that comes after 27 and before 29. It is an even number divisible by 2. In decimal notation, 28 is written as "28."

In mathematics, 28 is classified as a perfect number. A perfect number is defined as a positive integer that is equal to the sum of its proper divisors (a divisor of a number that is less than the number itself). The proper divisors of 28 are 1, 2, 4, 7, and 14. When these numbers are added together (1 + 2 + 4 + 7 + 14), the result is 28.

In Roman numerals, 28 is represented as "XXVIII."

In the Gregorian calendar, the year 28 BC is significant as it marks the year before the commonly accepted birth of Jesus Christ. The year 2028 AD will be a leap year in the Gregorian calendar, which means it will have one extra day (February 29) compared to a regular year.

The number 28 is often used in symbolism and culture. For example, the 28th wedding anniversary is traditionally associated with the theme of orchids. In some cultures, it is considered a lucky number associated with success and prosperity.

28 is also connected to various phenomena in science and technology. For instance, 28 is the atomic number of nickel, a chemical element. Additionally, 28 days is the average length of a lunar month, which represents the time it takes for the moon to orbit the Earth.

In popular culture, the number 28 is referenced in movies, books, and music. For example, the film "28 Days Later" is a popular zombie apocalypse movie released in 2002. The number is also mentioned in songs like "28 Days" by Aceyalone and "28" by The Weeknd.