number.wiki

Number

1,181

1,181 is a prime, odd, a calendar year.

Arithmetic Number Deficient Number Emirp Evil Number Flippable Prime Pythagorean Prime Recamán's Sequence Sexy Prime Squarefree Year

Historical context — 1181 AD

Calendar year

Year 1181 (MCLXXXI) was a common year starting on Thursday of the Julian calendar.

Excerpt from Wikipedia (en) ↗ · Licensed CC BY-SA 4.0 · English fallback Read the full article on Wikipedia →

Year facts

Year type: Common year
Standard 365-day year; not divisible by 4 (or divisible by 100 but not 400).
Days in year: 365
ISO weeks: 53
Long year: contains 53 ISO weeks.
Started on: Thursday
January 1, 1181
Ended on: Thursday
December 31, 1181
Friday the 13ths: 3
3 Friday the 13ths this year.
Decade: 1180s
1180–1189
Century: 12th century
1101–1200
Millennium: 2nd millennium
1001–2000
Years ago: 845
845 years before 2026.

In other calendars

Hebrew: 4941 / 4942 AM
Rosh Hashanah falls in September/October.
Islamic Hijri: 576 / 577 AH
Lunar calendar; year spans differ from Gregorian.
Chinese: Year of the zodiac:Metal zodiac:Ox
Sexagenary cycle position 38 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era: 1724 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Persian Solar Hijri: 559 / 560 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
Ethiopian: 1173 / 1174 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): 1103 / 1102 Saka
Indian national calendar; year starts in March.

Properties

Parity: Odd
Digit count: 4
Digit sum: 11
Digit product: 8
Digital root: 2
Palindrome: No
Bit width: 11 bits
Reversed: 1,811
Flips to (rotate 180°): 1,811
Recamán's sequence: a(30,546) = 1,181
Square (n²): 1,394,761
Cube (n³): 1,647,212,741
Divisor count: 2
σ(n) — sum of divisors: 1,182
φ(n) — Euler's totient: 1,180

Primality

1,181 is prime. It has exactly two divisors: 1 and itself.

Divisors & multiples

All divisors (2)

1 · 1181

Aliquot sum (sum of proper divisors): 1

Factor pairs (a × b = 1,181)

1 × 1181

First multiples

1,181 · 2,362 (double) · 3,543 · 4,724 · 5,905 · 7,086 · 8,267 · 9,448 · 10,629 · 11,810

Sums & aliquot sequence

As a sum of two squares: 5² + 34²

As consecutive integers: 590 + 591

Representations

In words: one thousand one hundred eighty-one
Ordinal: 1181st
Roman numeral: MCLXXXI
Binary: 10010011101
Octal: 2235
Hexadecimal: 0x49D
Base64: BJ0=
One's complement: 64,354 (16-bit)

In other bases

ternary (3) 1121202

quaternary (4) 102131

quinary (5) 14211

senary (6) 5245

septenary (7) 3305

nonary (9) 1552

undecimal (11) 984

duodecimal (12) 825

tridecimal (13) 6cb

tetradecimal (14) 605

pentadecimal (15) 53b

Historical numeral systems

Babylonian (base 60): 𒌋𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒁹
Egyptian hieroglyphic: 𓆼𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓏺
Greek (Milesian): ͵αρπαʹ
Mayan (base 20): 𝋢·𝋳·𝋡
Chinese: 一千一百八十一
Chinese (financial): 壹仟壹佰捌拾壹

In other modern scripts

Eastern Arabic ١١٨١ Devanagari ११८१ Bengali ১১৮১ Tamil ௧௧௮௧ Thai ๑๑๘๑ Tibetan ༡༡༨༡ Khmer ១១៨១ Lao ໑໑໘໑ Burmese ၁၁၈၁

Digit at this position in famous constants

π — Pi (π): Digit 1,181 = 7
e — Euler's number (e): Digit 1,181 = 5
φ — Golden ratio (φ): Digit 1,181 = 4
√2 — Pythagoras's (√2): Digit 1,181 = 7
ln 2 — Natural log of 2: Digit 1,181 = 8
γ — Euler-Mascheroni (γ): Digit 1,181 = 3

Also seen as

Prime neighborhood

Adjacent primes:

Previous prime: 1,171 (gap of 10)
Next prime: 1,187 (gap of 6)

Pair status: sexy with 1187.

Unicode codepoint

ҝ

Cyrillic Small Letter Ka With Vertical Stroke

U+049D

Lowercase letter (Ll)

UTF-8 encoding: D2 9D (2 bytes).

Lookup U+049D on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#00049D

RGB(0, 4, 157)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.4.157.

Address: 0.0.4.157
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.4.157

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

Position in π

The digit sequence 1181 first appears in π at position 11,914 of the decimal expansion (the 11,914ordinal-suffix:th digit after the integer 3).

Search range: the first 1,000,000 fractional digits of π. Any 6-digit-or-shorter string is virtually guaranteed to appear in there — the more interesting signal is the position.

Look up 1181 on Pi Search ↗