13 (number)

← 12 13 14 →
← 10 11 12 13 14 15 16 17 18 19 → List of numbers; Integers; ← 0 10 20 30 40 50 60 70 80 90 →
Cardinal	thirteen
Ordinal	13th; (thirteenth)
Numeral system	tredecimal
Factorization	prime
Prime	6th
Divisors	1, 13
Greek numeral	ΙΓ´
Roman numeral	XIII
Binary	11012
Ternary	1113
Senary	216
Octal	158
Duodecimal	1112
Hexadecimal	D16
Hebrew numeral	י"ג
Babylonian numeral	𒌋𒐗

13 (thirteen) is the natural number following 12 and preceding 14.

Strikingly folkloric aspects of the number 13 have been noted in various cultures around the world: one theory is that this is due to the cultures employing lunar-solar calendars (there are approximately 12.41 lunations per solar year, and hence 12 "true months" plus a smaller, and often portentous, thirteenth month). This can be witnessed, for example, in the "Twelve Days of Christmas" of Western European tradition.^[1]

^ Frazier, King of the Bean, and the Festival of Fools. Cited in Thompson, Tok. 2002. The thirteenth number: Then, there/ here and now. Studia Mythological Slavica 5, 145–159.

[1] Frazier, King of the Bean, and the Festival of Fools. Cited in Thompson, Tok. 2002. The thirteenth number: Then, there/ here and now. Studia Mythological Slavica 5, 145–159.

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