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7th

← 6 7 8 →
−1 0 1 2 3 4 5 6 7 8 9
Cardinal seven
Ordinal 7th
(seventh)
Numeral system septenary
Factorization prime
Prime 4th
Divisors 1, 7
Roman numeral VII
Roman numeral (unicode) Ⅶ, ⅶ
Greek prefix /
Latin prefix
Binary 1112
Ternary 213
Quaternary 134
Quinary 125
Senary 116
Octal 78
Duodecimal 712
Hexadecimal 716
Vigesimal 720
Base 36 736
Greek numeral Z, ζ
Amharic
Arabic ٧
Persian & Kurdish ٧
Urdu ۷
Bengali
Chinese numeral 七(qi)
Devanāgarī (sat)
Telugu
Tamil
Hebrew ז (Zayin)
Khmer
Thai
Saraiki ٧
Kannada

7 (seven; /ˈsɛvən/) is the natural number following 6 and preceding 8.

In the beginning, various Hindus wrote 7 more or less in one stroke as a curve that looks like an uppercase J vertically inverted. The western Ghubar Arabs' main contribution was to make the longer line diagonal rather than straight, though they showed some tendencies to making the character more rectilinear. The eastern Arabs developed the character from a 6-look-alike into an uppercase V-look-alike. Both modern Arab forms influenced the European form, a two-stroke character consisting of a horizontal upper line joined at its right to a line going down to the bottom left corner, a line that is slightly curved in some font variants. As is the case with the European glyph, the Cham and Khmer glyph for 7 also evolved to look like their glyph for 1, though in a different way, so they were also concerned with making their 7 more different. For the Khmer this often involved adding a horizontal line above the glyph. This is analogous to the horizontal stroke through the middle that is sometimes used in handwriting in the Western world but which is almost never used in computer fonts. This horizontal stroke is, however, important to distinguish the glyph for seven from the glyph for one in writings that use a long upstroke in the glyph for 1. In some Greek dialects of early 12th century the longer line diagonal was drawn in a rather semicircular transverse line.

On the seven-segment displays of pocket calculators and digital watches, 7 is the number with the most common glyph variation (1, 6 and 9 also have variant glyphs). Most calculators use three line segments, but on Sharp, Casio, and a few other brands of calculators, 7 is written with four line segments because, in Japan, Korea and Taiwan 7 is written as ① in the illustration to the right.


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Wikipedia

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