Nombre

13

13 — Thirteen

13 is a prime, odd, a calendar year.

Thirteen is the sixth prime and is widely considered unlucky in many Western cultures (a phenomenon called triskaidekaphobia). It is also the smallest emirp — a prime whose digit reversal (31) is a different prime.

Sources https://en.wikipedia.org/wiki/13_(number)

Cousin Prime Curated Deficient Number Fibonacci Happy Number Prime Recamán's Sequence Sexy Prime Squarefree Twin Prime

Propriétés

Parité: Impair
Nombre de chiffres: 2
Somme des chiffres: 4
Racine numérique: 4
Palindrome: Non
Inversé: 31
Suite de Recamán: a(6) = 13
Nombre de diviseurs: 2
σ(n) — somme des diviseurs: 14

Primalité

13 is prime. It has exactly two divisors: 1 and itself.

Diviseurs et multiples

All divisors (2)

1 · 13

Aliquot sum (sum of proper divisors): 1

Factor pairs (a × b = 13)

1 × 13

First multiples

13 · 26 · 39 · 52 · 65 · 78 · 91 · 104 · 117 · 130

Représentations

En lettres: thirteen
Ordinal: 13th
Chiffre romain: XIII
Binaire: 1101
Octal: 15
Hexadécimal: 0xD
Base64: DQ==

Aussi vu comme

Prime neighborhood

Adjacent primes:

Previous prime: 11 (gap of 2)
Next prime: 17 (gap of 4)

Pair status: twin with 11, cousin with 17.

ASCII character

As an ASCII codepoint, 13 is CR (carriage return). ASCII control character.

Hex color

#00000D

RGB(0, 0, 13)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.0.13.

Address: 0.0.0.13
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.0.13

Unspecified address (0.0.0.0/8) — "this network" placeholder.

Possible US bank routing number

This passes the ABA routing number checksum and matches the Federal Reserve numbering scheme.

Routing number

000000013

Federal Reserve

United States Government

Banks operate many routing numbers per state and division; an unmatched checksum-valid number can still be a real RTN at a smaller institution.

Look up 000000013 on FedACH ↗ Routing Number Lookup (Wise) ↗