13 (number)

← 12 13 14 →
Cardinalthirteen
Ordinal13th
(thirteenth)
Numeral systemtredecimal
Factorizationprime
Prime6th
Divisors1, 13
Greek numeralΙΓ´
Roman numeralXIII
Binary11012
Ternary1113
Senary216
Octal158
Duodecimal1112
HexadecimalD16
Hebrew numeralי"ג
Babylonian numeral𒌋𒐗

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

Folklore surrounding the number 13 appears in many 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]

  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.