Number

266

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

Arithmetic Number Deficient Number Harshad / Niven Odious Number Pernicious Number Recamán's Sequence Self Number Sphenic Number Squarefree Year

Historical context — 266 AD

Calendar year

Year 266 (CCLXVI) was a common year starting on Monday of the Julian calendar.

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Historical context — 266 BC

Calendar year

Year 266 BC was a year of the pre-Julian Roman 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: Monday
January 1, 266
Ended on: Monday
December 31, 266
Friday the 13ths: 2
2 Friday the 13ths this year.
Decade: 260s
260–269
Century: 3rd century
201–300
Millennium: 1st millennium
1–1000
Years ago: 1,760
1760 years before 2026.

In other calendars

Hebrew: 4026 / 4027 AM
Rosh Hashanah falls in September/October.
Chinese: Year of the zodiac:Fire zodiac:Dog
Sexagenary cycle position 23 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era: 809 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Ethiopian: 258 / 259 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): 188 / 187 Saka
Indian national calendar; year starts in March.

Properties

Parity: Even
Digit count: 3
Digit sum: 14
Digit product: 72
Digital root: 5
Palindrome: No
Bit width: 9 bits
Reversed: 662
Recamán's sequence: a(187) = 266
Square (n²): 70,756
Cube (n³): 18,821,096
Divisor count: 8
σ(n) — sum of divisors: 480
φ(n) — Euler's totient: 108
Sum of prime factors: 28

Primality

Prime factorization: 2 × 7 × 19

Nearest primes: 263 (−3) · 269 (+3)

Divisors & multiples

All divisors (8)

1 · 2 · 7 · 14 · 19 · 38 · 133 (half) · 266

Aliquot sum (sum of proper divisors): 214

Factor pairs (a × b = 266)

1 × 266

2 × 133

7 × 38

14 × 19

First multiples

266 · 532 (double) · 798 · 1,064 · 1,330 · 1,596 · 1,862 · 2,128 · 2,394 · 2,660

Sums & aliquot sequence

As consecutive integers: 65 + 66 + 67 + 68 35 + 36 + … + 41 5 + 6 + … + 23

Aliquot sequence: 266 → 214 → 110 → 106 → 56 → 64 → 63 → 41 → 1 → 0 — terminates at zero

Representations

In words: two hundred sixty-six
Ordinal: 266th
Roman numeral: CCLXVI
Binary: 100001010
Octal: 412
Hexadecimal: 0x10A
Base64: AQo=
One's complement: 65,269 (16-bit)

In other bases

ternary (3) 100212

quaternary (4) 10022

quinary (5) 2031

senary (6) 1122

septenary (7) 530

nonary (9) 325

undecimal (11) 222

duodecimal (12) 1a2

tridecimal (13) 176

tetradecimal (14) 150

pentadecimal (15) 12b

Historical numeral systems

Babylonian (base 60): 𒁹𒁹𒁹𒁹 𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹
Egyptian hieroglyphic: 𓍢𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓏺𓏺𓏺𓏺𓏺𓏺
Greek (Milesian): σξϛʹ
Mayan (base 20): 𝋭·𝋦
Chinese: 二百六十六
Chinese (financial): 貳佰陸拾陸

In other modern scripts

Eastern Arabic ٢٦٦ Devanagari २६६ Bengali ২৬৬ Tamil ௨௬௬ Thai ๒๖๖ Tibetan ༢༦༦ Khmer ២៦៦ Lao ໒໖໖ Burmese ၂၆၆

Digit at this position in famous constants

π — Pi (π): Digit 266 = 3
e — Euler's number (e): Digit 266 = 4
φ — Golden ratio (φ): Digit 266 = 7
√2 — Pythagoras's (√2): Digit 266 = 3
ln 2 — Natural log of 2: Digit 266 = 0
γ — Euler-Mascheroni (γ): Digit 266 = 7

Also seen as

Goldbach decomposition

Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 266, here are decompositions:

3 + 263 = 266
37 + 229 = 266
43 + 223 = 266
67 + 199 = 266
73 + 193 = 266
103 + 163 = 266
109 + 157 = 266
127 + 139 = 266

Showing the first eight; more decompositions exist.

Unicode codepoint

Latin Capital Letter C With Dot Above

U+010A

Uppercase letter (Lu)

UTF-8 encoding: C4 8A (2 bytes).

Lookup U+010A on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#00010A

RGB(0, 1, 10)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.1.10.

Address: 0.0.1.10
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.1.10

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