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Number

2,081

2,081 is a prime, odd, a calendar year.

Arithmetic Number Chen Prime Deficient Number Odious Number Pernicious Number Prime Pythagorean Prime Recamán's Sequence Sexy Prime Squarefree Twin Prime Year

Historical context — 2081 AD

Current millennium spanning the years 2001 to 3000

The third millennium of the Anno Domini or Common Era is the current millennium spanning the years 2001 to 3000.

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
52
Started on
Wednesday
January 1, 2081
Ended on
Wednesday
December 31, 2081
Friday the 13ths
1
One Friday the 13th this year.
Easter Sunday
March 30
Sunday, March 30, 2081
Decade
2080s
2080–2089
Century
21st century
2001–2100
Millennium
3rd millennium
2001–3000
Years until
55
55 years after 2026.

In other calendars

Hebrew
5841 / 5842 AM
Rosh Hashanah falls in September/October.
Islamic Hijri
1504 / 1505 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
2624 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Persian Solar Hijri
1459 / 1460 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
Ethiopian
2073 / 2074 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka)
2003 / 2002 Saka
Indian national calendar; year starts in March.
Japanese
Reiwa 63
Reign-era counting from the start of each emperor's reign.

Properties

Parity
Odd
Digit count
4
Digit sum
11
Digit product
0
Digital root
2
Palindrome
No
Bit width
12 bits
Reversed
1,802
Recamán's sequence
a(3,589) = 2,081
Square (n²)
4,330,561
Cube (n³)
9,011,897,441
Divisor count
2
σ(n) — sum of divisors
2,082
φ(n) — Euler's totient
2,080

Primality

2,081 is prime. It has exactly two divisors: 1 and itself.

Divisors & multiples

All divisors (2)
1 · 2081
Aliquot sum (sum of proper divisors): 1
Factor pairs (a × b = 2,081)
1 × 2081
First multiples
2,081 · 4,162 (double) · 6,243 · 8,324 · 10,405 · 12,486 · 14,567 · 16,648 · 18,729 · 20,810

Sums & aliquot sequence

As a sum of two squares: 20² + 41²
As consecutive integers: 1,040 + 1,041

Representations

In words
two thousand eighty-one
Ordinal
2081st
Roman numeral
MMLXXXI
Binary
100000100001
Octal
4041
Hexadecimal
0x821
Base64
CCE=
One's complement
63,454 (16-bit)
In other bases
ternary (3) 2212002
quaternary (4) 200201
quinary (5) 31311
senary (6) 13345
septenary (7) 6032
nonary (9) 2762
undecimal (11) 1622
duodecimal (12) 1255
tridecimal (13) c41
tetradecimal (14) a89
pentadecimal (15) 93b

Historical numeral systems

Babylonian (base 60)
𒌋𒌋𒌋𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒁹
Egyptian hieroglyphic
𓆼𓆼𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓏺
Greek (Milesian)
͵βπαʹ
Mayan (base 20)
𝋥·𝋤·𝋡
Chinese
二千零八十一
Chinese (financial)
貳仟零捌拾壹
In other modern scripts
Eastern Arabic ٢٠٨١ Devanagari २०८१ Bengali ২০৮১ Tamil ௨௦௮௧ Thai ๒๐๘๑ Tibetan ༢༠༨༡ Khmer ២០៨១ Lao ໒໐໘໑ Burmese ၂၀၈၁

Digit at this position in famous constants

π — Pi (π)
Digit 2,081 = 1
e — Euler's number (e)
Digit 2,081 = 5
φ — Golden ratio (φ)
Digit 2,081 = 2
√2 — Pythagoras's (√2)
Digit 2,081 = 0
ln 2 — Natural log of 2
Digit 2,081 = 3
γ — Euler-Mascheroni (γ)
Digit 2,081 = 0

Also seen as

Prime neighborhood

Adjacent primes:

  • Previous prime: 2,069 (gap of 12)
  • Next prime: 2,083 (gap of 2)

Pair status: twin with 2083.

Unicode codepoint
Samaritan Vowel Sign Overlong A
U+0821
Non-spacing mark (Mn)

UTF-8 encoding: E0 A0 A1 (3 bytes).

Hex color
#000821
RGB(0, 8, 33)
IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.8.33.

Address
0.0.8.33
Class
reserved
IPv4-mapped IPv6
::ffff:0.0.8.33

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

Position in π

The digit sequence 2081 first appears in π at position 14,769 of the decimal expansion (the 14,769ordinal-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.