number.wiki
Number

1,266

1,266 is a composite number, even, a calendar year.

Abundant Number Arithmetic Number Evil Number Recamán's Sequence Semiperfect Number Sphenic Number Squarefree Year

Historical context — 1266 AD

Calendar year

Year 1266 (MCCLXVI) was a common year starting on Friday 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
52
Started on
Friday
January 1, 1266
Ended on
Friday
December 31, 1266
Friday the 13ths
1
One Friday the 13th this year.
Decade
1260s
1260–1269
Century
13th century
1201–1300
Millennium
2nd millennium
1001–2000
Years ago
760
760 years before 2026.

In other calendars

Hebrew
5026 / 5027 AM
Rosh Hashanah falls in September/October.
Islamic Hijri
664 / 665 AH
Lunar calendar; year spans differ from Gregorian.
Chinese
Year of the zodiac:Fire zodiac:Tiger
Sexagenary cycle position 3 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era
1809 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Persian Solar Hijri
644 / 645 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
Ethiopian
1258 / 1259 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka)
1188 / 1187 Saka
Indian national calendar; year starts in March.

Properties

Parity
Even
Digit count
4
Digit sum
15
Digit product
72
Digital root
6
Palindrome
No
Bit width
11 bits
Reversed
6,621
Recamán's sequence
a(8,456) = 1,266
Square (n²)
1,602,756
Cube (n³)
2,029,089,096
Divisor count
8
σ(n) — sum of divisors
2,544
φ(n) — Euler's totient
420
Sum of prime factors
216

Primality

Prime factorization: 2 × 3 × 211

Nearest primes: 1,259 (−7) · 1,277 (+11)

Divisors & multiples

All divisors (8)
1 · 2 · 3 · 6 · 211 · 422 · 633 (half) · 1266
Aliquot sum (sum of proper divisors): 1,278
Factor pairs (a × b = 1,266)
1 × 1266
2 × 633
3 × 422
6 × 211
First multiples
1,266 · 2,532 (double) · 3,798 · 5,064 · 6,330 · 7,596 · 8,862 · 10,128 · 11,394 · 12,660

Sums & aliquot sequence

As consecutive integers: 421 + 422 + 423 315 + 316 + 317 + 318 100 + 101 + … + 111
Aliquot sequence: 1,266 1,278 1,530 2,682 3,168 6,660 14,088 21,192 31,848 47,832 71,808 148,512 359,520 946,848 1,895,712 4,539,360 12,180,336 — unresolved within range

Representations

In words
one thousand two hundred sixty-six
Ordinal
1266th
Roman numeral
MCCLXVI
Binary
10011110010
Octal
2362
Hexadecimal
0x4F2
Base64
BPI=
One's complement
64,269 (16-bit)
In other bases
ternary (3) 1201220
quaternary (4) 103302
quinary (5) 20031
senary (6) 5510
septenary (7) 3456
nonary (9) 1656
undecimal (11) a51
duodecimal (12) 896
tridecimal (13) 765
tetradecimal (14) 666
pentadecimal (15) 596

Historical numeral systems

Babylonian (base 60)
𒌋𒌋𒁹 𒁹𒁹𒁹𒁹𒁹𒁹
Egyptian hieroglyphic
𓆼𓍢𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓏺𓏺𓏺𓏺𓏺𓏺
Greek (Milesian)
͵ασξϛʹ
Mayan (base 20)
𝋣·𝋣·𝋦
Chinese
一千二百六十六
Chinese (financial)
壹仟貳佰陸拾陸
In other modern scripts
Eastern Arabic ١٢٦٦ Devanagari १२६६ Bengali ১২৬৬ Tamil ௧௨௬௬ Thai ๑๒๖๖ Tibetan ༡༢༦༦ Khmer ១២៦៦ Lao ໑໒໖໖ Burmese ၁၂၆၆

Digit at this position in famous constants

π — Pi (π)
Digit 1,266 = 2
e — Euler's number (e)
Digit 1,266 = 5
φ — Golden ratio (φ)
Digit 1,266 = 4
√2 — Pythagoras's (√2)
Digit 1,266 = 9
ln 2 — Natural log of 2
Digit 1,266 = 9
γ — Euler-Mascheroni (γ)
Digit 1,266 = 4

Also seen as

Goldbach decomposition

Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 1266, here are decompositions:

  • 7 + 1259 = 1266
  • 17 + 1249 = 1266
  • 29 + 1237 = 1266
  • 37 + 1229 = 1266
  • 43 + 1223 = 1266
  • 53 + 1213 = 1266
  • 73 + 1193 = 1266
  • 79 + 1187 = 1266

Showing the first eight; more decompositions exist.

Unicode codepoint
Ӳ
Cyrillic Capital Letter U With Double Acute
U+04F2
Uppercase letter (Lu)

UTF-8 encoding: D3 B2 (2 bytes).

Hex color
#0004F2
RGB(0, 4, 242)
IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.4.242.

Address
0.0.4.242
Class
reserved
IPv4-mapped IPv6
::ffff:0.0.4.242

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

Position in π

The digit sequence 1266 first appears in π at position 4,160 of the decimal expansion (the 4,160ordinal-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.