# 1

1 (one, also called unit, unity, and (multiplicative) identity) is a number, numeral, and glyph. It represents a single entity, the unit of counting or measurement. For example, a line segment of unit length is a line segment of length 1. It is also the first of the infinite sequence of natural numbers, followed by 2

- 31 (number)
- 31 (thirty-one) is the natural number following 30 and preceding 32
- 26 (number)
- 26 (twenty-six) is the natural number following 25 and preceding 27
- 10
- 10 (ten) is an even natural number following 9 and preceding 11. Ten is the base of the decimal numeral system, by far the most common system of denoting numbers in both spoken and written language. The reason for the choice of ten is assumed to be that
- 9
- 9 (nine) is the natural number following 8 and preceding 10
- 8
- 8 (eight) is the natural number following 7 and preceding 9
- 6
- 6 (six) is the natural number following 5 and preceding 7. The SI prefix for 10006 is exa- (E), and for its reciprocal atto- (a
- 5
- 5 (five) is a number, numeral, and glyph. It is the natural number following 4 and preceding 6
- 2
- 2 (two) is a number, numeral, and glyph. It is the natural number following 1 and preceding 3
- 3
- 3 (three) is a number, numeral, and glyph. It is the natural number following 2 and preceding 4
- 4
- 4 (four) is a number, numeral, and glyph. It is the natural number following 3 and preceding 5