Cardinal7 sevenOrdinal7th seventhNumeral systemseptenaryFactorizationprimeDivisors1, 7Roman numeralVIIRoman character (Unicode)Ⅶ, ⅶAmharic፯Indian٧Bengali৭Chinese numeral七，柒Devanāgarī७Hebrewז (Zayin)Khmer៧Thai๗prefixeshepta-/hept- (from Greek)

septua- (from Latin)

7 (seven) is a number, numeral, and also glyph that represents the number. It is the organic number<1> that adheres to 6 and precedes 8. That is an integer and also a cardinal number, the is, a number the is used for counting.

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<2> In addition, that is classified as a genuine number,<3> separating it from imaginary numbers.

## Contents

2 In mathematics3 In science5 In religion

Seven days of production - 1765 book, title page

## Evolution that the glyph

In the beginning, assorted Hindus composed 7 an ext or much less in one stroke as a curve the looks choose an uppercase J upside down. The main contribution that the western Ghubar Arabs to be to make the longer line diagonal quite than straight, despite they verified some tendencies to making the character more rectilinear. The east Arabs arisen the character from a 6-look-alike into an uppercase V-look-alike. Both modern Arab forms influenced the europe form, a two-stroke personality consisting the a horizontal top line join at its best to a heat going down to the bottom left corner, a line the is slightly curved in some font variants.

As to be the instance with the europe glyph, the Cham and also Khmer glyph for 7 likewise evolved come look favor their glyph for 1, despite in a various way, for this reason they were additionally concerned around making your 7 an ext different. For the Khmer, this regularly involved including a horizontal line above the glyph.<4> This is analogous to the horizontal stroke with the center that is periodically used in handwriting in the west world, yet it is virtually never supplied in computer system fonts. This horizontal punch is, however, vital to identify the glyph for seven from the glyph because that one in works that usage a lengthy upstroke in the glyph because that one.

On the seven-segment displays of pocket calculators and digital watches, 7 is the number with the most typical glyph sports (0, 6 and 9 additionally have variant glyphs). Most calculators use 3 line segments, yet in part brands that calculators, 7 is composed with 4 line segments. The factor is that in Japan and also Korea, 7 is created as ① in the illustration to the right.

While the shape of the 7 character has actually an ascender in most modern-day typefaces, in typefaces v text numbers the personality usually has a descender, because that example, in

.

Some people, specifically in Europe and also Latin America, create 7 through a heat in the middle and also make the peak line crooked. The line v the middle is advantageous to plainly differentiate the character from the number one, as these deserve to appear comparable when written in particular styles the handwriting.

## In mathematics

Seven is a Mersenne prime, because 23 - 1 = 7Seven is both a Carol number and a Kynea numberSeven is the 4th prime number, the 2nd lucky prime, and the second safe primeSeven is the very first Newman-Shanks-Williams primeSeven is the first Woodall primeSeven is the fourth factorial primeSeven is the fourth Mersenne prime exponentSeven is the third Lucas primeSeven is the fourth self numberSeven is the just number less than 15 that cannot be represented as the sum of the squares of 3 integersSeven is the smallest happy number, except for the trivial instance of 17 is the just dimension, besides the acquainted 3, in i beg your pardon a vector cross product can be definedA team of seven is dubbed a heptadA seven-sided form is a heptagon. The continual n-gons because that n ≤ 6 deserve to be constructed by compass and straightedge alone, yet the constant heptagon cannot. Figurate number representing heptagons (including seven) are called heptagonal numbers. 7 is additionally a centered hexagonal number.

### In numeral systems

BaseNumeral system
2binary111
3ternary21
4quaternary13
5quinary12
6senary11
7septenary10
over 7 (octal, decimal, and also so on)7

In quaternary, 7 is the the smallest prime v a composite sum of digits.

In the English language, 7 is the only 2-syllable natural, hopeful 1-digitnumber7 is the sixth number of the alphabet

### List of basic calculations

Multiplication12345678910111213141516171819202122232425501001000
7×xdisplaystyle 7 imes x
7142128354249566370778491981051121191261331401471541611681753507007000
Division123456789101112131415
7÷xdisplaystyle 7div x
73.52.3¯displaystyle 2.overline 3
1.751.41.16¯displaystyle 1.1overline 6
10.8750.7¯displaystyle 0.overline 7
0.7
0.63¯displaystyle 0.overline 63
0.583¯displaystyle 0.58overline 3
0.538461¯displaystyle 0.overline 538461
0.50.46¯displaystyle 0.4overline 6
x÷7displaystyle xdiv 7
0.142857¯displaystyle 0.overline 142857
0.285714¯displaystyle 0.overline 285714
0.428571¯displaystyle 0.overline 428571
0.571428¯displaystyle 0.overline 571428
0.714285¯displaystyle 0.overline 714285
0.857142¯displaystyle 0.overline 857142
11.142857¯displaystyle 1.overline 142857
1.285714¯displaystyle 1.overline 285714
1.428571¯displaystyle 1.overline 428571
1.571428¯displaystyle 1.overline 571428
1.714285¯displaystyle 1.overline 714285
1.857142¯displaystyle 1.overline 857142
22.142857¯displaystyle 2.overline 142857
Exponentiation12345678910111213
7xdisplaystyle 7^x,
74934324011680711764982354357648014035360728247524919773267431384128720196889010407
x7displaystyle x^7,
15137 displaystyle 13_7
217 displaystyle 21_7
267 displaystyle 26_7
347 displaystyle 34_7
427 displaystyle 42_7
557 displaystyle 55_7
1017 displaystyle 101_7
1147 displaystyle 114_7
1307 displaystyle 130_7
1437 displaystyle 143_7
1567 displaystyle 156_7
2027 displaystyle 202_7
2157 displaystyle 215_7
2317 displaystyle 231_7
2447 displaystyle 244_7
2607 displaystyle 260_7
3037 displaystyle 303_7
4047 displaystyle 404_7
5057 displaystyle 505_7
13137 displaystyle 1313_7
26267 displaystyle 2626_7
411047 displaystyle 41104_7
5643557 displaystyle 564355_7
113333117 displaystyle 11333311_7

## In science

### Physics

Arranging corpuscle by fee from an adverse to positive and interpreting your charges as integer multiples of one elementary charge e* (1/3 e) one gets the following seven charges establish in nature:
 3. Generation τ- anti-t b-quark anti-b t-quark τ+ 2. Generation μ- anti-c s-quark anti-s c-quark μ+ 1. Generation e- anti-u d-quark anti-d u-quark e+ 0. Generation stem particle charge -3/3 -2/3 -1/3 0 +1/3 +2/3 +3/3 angular spin -3 -2 -1 0 +1 +2 +3

It is evident that a the contrary exists v no electromagnetic charge. It is suspect here, that the dimension of fee is linearly dependency on the number of quanta the angular turn generating it. In the state of symmetry no magnetic ingredient is generated since no angular spin exists. A particle in together a supersymmetric state would be dark because it can not electromagnetically interact. Breaking of supersymmetry the this topologically substructured superstring fragment would be a adjust of that is angular spin, generating equivalent particles that physics in dependence of the power level. This angular spin not just generates charge however highly non-linearly additionally gravo-magnetic mass in dependence of string stress and anxiety (energy). There appears to be just one generic unique geometry v a addressed functionality the a weak communicating superstring dark stem particle.(0. Generation).

In generations one to 3 there room two set of 3 physical particles through opposite fee according to the direction the angular spin. Because that all 3 generations just two geometrically and also functionally the same dark stem particles exist. These just differ by your handedness, generating matter and also antimatter corpuscle on break of 0-spin symmetry.

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The incident of matter and antimatter corpuscle is asymmetric through respect come this symmetry, -3 -1 +2 for matter and -2 +1 +3 for antimatter. Both to adjust of three particles space arranged in a complementary way around the symmetry allowed by this worldwide physical realization of the number seven. Therefore the number seven just emerges as a security superposition of two sets of physical particles that are created by break of a supersymmetric state. Nature just makes use of the symmetry detailed by the number seven. It however does no actually realize it. Seven seems to be much more "constructed" by arranging two sets of reality representing the number three approximately a state of symmetry.

### Biology

Seven is the variety of external feet in the human being head: two eyes, 2 nostrils, one mouth, two earsThere room 7 spots on a common ladybug

### Astronomy

In Indian astronomy, seven saints appear in a constellation referred to as "Saptharishi Mandalam"7 main stars consist of the constellation that The huge DipperThe Roman numeral VII (usually) means the seventh-discovered satellite that a earth or minor planet (for example, Jupiter VII)