6 (number)

6 is a natural number that follows 5 and precedes 7. It is used in counting, measurement, and ordering (the sixth position). The symbol '6' derives from the Hindu-Arabic numerals, which are the most widely used writing system for numbers in the world today.

In the decimal system, 6 is a single digit. In the binary system it is 110. It is an even number divisible by 2 with no remainder.

Mathematical properties

The divisors of 6 are 1, 2, 3, and 6. It is a composite number, as it has divisors other than 1 and itself; it is the product of 2 × 3, both of which are prime numbers.

6 is called a perfect number: the sum of its proper divisors—1 + 2 + 3—equals 6 itself. It is the smallest number with this property; the next is 28. Additionally, 6 is the product 1 × 2 × 3, known as the factorial of 3 (3!), and is a triangular number as it equals 1 + 2 + 3.

Geometry

The six-sided polygon is called a hexagon; each interior angle of a regular hexagon is 120 degrees. Regular hexagons can fill a plane with no gaps, as seen in the structure of honeycomb. A cube has six square faces, which is why six-sided dice typically bear the numbers 1 through 6.

Uses and examples

In systems of time and measurement, 6 is an important base: 60 seconds make a minute, and 60 minutes make an hour, following the sexagesimal system of ancient Babylon. In chemistry, 6 is the atomic number of carbon. In music, 'six' refers to an interval called a sixth. In sports, a football team has 11 players on the field, but a volleyball team has six players on the court.