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Zahl

7

7 — Seven

7 is a prime, odd, a calendar year.

Seven is the fourth prime number and the lowest natural number that cannot be represented as the sum of the squares of three integers. It appears repeatedly across cultures: seven days of the week, seven wonders of the ancient world, seven deadly sins.

Quellen https://en.wikipedia.org/wiki/7
Cousin Prime Curated Deficient Number Happy Number Harshad / Niven Heptagonal Lucas Mersenne Prime Narcissistic / Armstrong Prime Recamán's Sequence Sexy Prime Squarefree Twin Prime

Eigenschaften

Parität
Ungerade
Stellenanzahl
1
Quersumme
7
Iterierte Quersumme
7
Palindrom
Ja
Recamán-Folge
a(5) = 7
Anzahl der Teiler
2
σ(n) — Summe der Teiler
8

Primzahleigenschaft

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

Teiler und Vielfache

All divisors (2)
1 · 7
Aliquot sum (sum of proper divisors): 1
Factor pairs (a × b = 7)
1 × 7
First multiples
7 · 14 · 21 · 28 · 35 · 42 · 49 · 56 · 63 · 70

Darstellungen

In Worten
seven
Ordinal
7th
Römische Zahl
VII
Binär
111
Oktal
7
Hexadezimal
0x7
Base64
Bw==

Auch zu sehen als

Prime neighborhood

Adjacent primes:

  • Previous prime: 5 (gap of 2)
  • Next prime: 11 (gap of 4)

Pair status: twin with 5, cousin with 11.

ASCII character

As an ASCII codepoint, 7 is BEL (bell). ASCII control character.

Hex color
#000007
RGB(0, 0, 7)
IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.0.7.

Address
0.0.0.7
Class
reserved
IPv4-mapped IPv6
::ffff:0.0.0.7

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