31s

The number 31 has several notable appearances and significances in various fields. In mathematics, 31 is a prime number, meaning it has no positive divisors other than 1 and itself. It is also the 10th Mersenne prime, a prime number that can be written in the form 2^n - 1. In the decimal system, 31 is the smallest number that cannot be expressed as the sum of two or more distinct non-zero triangular numbers.

In the Gregorian calendar, 31 is the number of days in the months of January, March, May, July, August, October, and December. It is also the number of days in the month of July, which is named after Julius Caesar, who introduced the Julian calendar in 46 BC.

In the English language, 31 is the number of letters in the alphabet. It is also the number of days in the month of January, which is the first month of the year.

In popular culture, 31 is the number of the card in a standard deck of playing cards that is known as the "Ace of Spades." It is also the number of the episode in the television series "The Twilight Zone" that is known as "The Monsters Are Due on Maple Street."

In the field of astronomy, 31 is the atomic number of the chemical element gallium. It is also the number of the asteroid 31 Euphrosyne, which was discovered in 1854.

In the field of music, 31 is the number of the key on a standard piano keyboard that is known as the "C sharp" or "D flat" key. It is also the number of the string on a standard guitar that is known as the "E string."

In the field of sports, 31 is the number that is worn by several notable athletes, including basketball player LeBron James and baseball player Babe Ruth. It is also the number of the team that is known as the "New York Giants" in the National Football League.