93 (number)

← 92 93 94 →
← 90 91 92 93 94 95 96 97 98 99 → List of numbers Integers ← 0 10 20 30 40 50 60 70 80 90 →
Cardinal	ninety-three
Ordinal	93rd (ninety-third)
Factorization	3 × 31
Divisors	1, 3, 31, 93
Greek numeral	ϞΓ´
Roman numeral	XCIII
Binary	10111012
Ternary	101103
Senary	2336
Octal	1358
Duodecimal	7912
Hexadecimal	5D16

93 (ninety-three) is the natural number following 92 and preceding 94.

In mathematics

93 is:

• the 28th distinct semiprime^[1] and the 9th of the form (3.q) where q is a higher prime.^[2]
• the first number in the 3rd triplet of consecutive semiprimes, 93, 94, 95.^[3]
• with an aliquot sum of 35; itself a semiprime, within an aliquot sequence (93,35,13,1,0) of three numbers to the Prime 13 in the 13-Aliquot tree.
• a Blum integer, since its two prime factors, 3 and 31 are both Gaussian primes.^[4]
• a repdigit in base 5 (333₅),^[5] and 30 (33₃₀).
• palindromic in bases 2, 5, and 30.
• a lucky number.^[6]
• a cake number.^[7]
• an idoneal number.^[8]

There are 93 different cyclic Gilbreath permutations on 11 elements,^[9] and therefore there are 93 different real periodic points of order 11 on the Mandelbrot set.^[10]

In other fields

Ninety-three is:

• The atomic number of neptunium, an actinide.
• The code for international direct dial phone calls to Afghanistan.
• One of two ISBN Group Identifiers for books published in India.
• The number of the French department Seine-Saint-Denis, a Paris suburb with high proportions of immigrants and low-income people, and as such used by many French rappers and those emulating their speech.^[11][12]

In classical Persian finger counting, the number 93 is represented by a closed fist. Because of this, classical Arab and Persian poets around 1 CE referred to someone's lack of generosity by saying that the person's hand made "ninety-three".^[13]

See also

• AD 93, a year in the Julian calendar
• List of highways numbered 93
• Ninety-Three (Quatrevingt-treize), a novel concerning the French Revolution by Victor Hugo
• 93 (Thelema), a greeting among Thelemites based on the numerological (gematric) value of Thelema (Will) and Agape (Love) in Greek letters.^[14]
• Babia 93, an album from a Pakistani pop singer Sajjad Ali
• London's 93 Feet East music venue
• Current 93, a musical project of David Tibet
• Los Angeles 93 KHJ radio
• United Airlines Flight 93, one of the airplanes hijacked on September 11, 2001.
• 93 'til Infinity, the debut album by Oakland hip hop group Souls of Mischief.

References

1. Sloane, N. J. A. (ed.). "Sequence A001358". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
2. Sloane, N. J. A. (ed.). "Sequence A001748". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
3. Sloane, N. J. A. (ed.). "Sequence A056809". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
4. Sloane, N. J. A. (ed.). "Sequence A016105". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
5. Sloane, N. J. A. (ed.). "Sequence A048330". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
6. Sloane, N. J. A. (ed.). "Sequence A000959". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
7. Sloane, N. J. A. (ed.). "Sequence A000125". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
8. Sloane, N. J. A. (ed.). "Sequence A000926". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
9. Sloane, N. J. A. (ed.). "Sequence A000048". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
10. Diaconis, Persi; Graham, Ron (2012), "Chapter 5: From the Gilbreath Principle to the Mandelbrot Set", Magical Mathematics: the mathematical ideas that animate great magic tricks, Princeton University Press, pp. 61–83.
11. Durand, Alain-Philippe (2002), Black, Blanc, Beur: Rap Music and Hip-Hop Culture in the Francophone World, Scarecrow Press, p. 55, ISBN 9780810844315.
12. Meltzer, Marisa; Shepherd, Julianne (March 2006), "Spitting Fire", Spin: 76–81.
13. Bloom, Jonathan M. (Spring 2002), "Hand sums: The ancient art of counting on your fingers", Boston College Magazine.
14. Campbell, Colin D. (2018). Thelema: an introduction to the life, work & philosophy of Aleister Crowley. Woodbury, Minnesota. ISBN 9780738755236.

External links

• On the Number 93