Number

278

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

Arithmetic Number Ascending Digits Deficient Number Evil Number Recamán's Sequence Semiprime Squarefree Year

Historical context — 278 AD

Calendar year

Year 278 (CCLXXVIII) was a common year starting on Tuesday of the Julian calendar.

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Historical context — 278 BC

Calendar year

Year 278 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: Tuesday
January 1, 278
Ended on: Tuesday
December 31, 278
Friday the 13ths: 2
2 Friday the 13ths this year.
Decade: 270s
270–279
Century: 3rd century
201–300
Millennium: 1st millennium
1–1000
Years ago: 1,748
1748 years before 2026.

In other calendars

Hebrew: 4038 / 4039 AM
Rosh Hashanah falls in September/October.
Chinese: Year of the zodiac:Earth zodiac:Dog
Sexagenary cycle position 35 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era: 821 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Ethiopian: 270 / 271 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): 200 / 199 Saka
Indian national calendar; year starts in March.

Properties

Parity: Even
Digit count: 3
Digit sum: 17
Digit product: 112
Digital root: 8
Palindrome: No
Bit width: 9 bits
Reversed: 872
Recamán's sequence: a(155) = 278
Square (n²): 77,284
Cube (n³): 21,484,952
Divisor count: 4
σ(n) — sum of divisors: 420
φ(n) — Euler's totient: 138
Sum of prime factors: 141

Primality

Prime factorization: 2 × 139

Nearest primes: 277 (−1) · 281 (+3)

Divisors & multiples

All divisors (4)

1 · 2 · 139 (half) · 278

Aliquot sum (sum of proper divisors): 142

Factor pairs (a × b = 278)

1 × 278

2 × 139

First multiples

278 · 556 (double) · 834 · 1,112 · 1,390 · 1,668 · 1,946 · 2,224 · 2,502 · 2,780

Sums & aliquot sequence

As consecutive integers: 68 + 69 + 70 + 71

Aliquot sequence: 278 → 142 → 74 → 40 → 50 → 43 → 1 → 0 — terminates at zero

Representations

In words: two hundred seventy-eight
Ordinal: 278th
Roman numeral: CCLXXVIII
Binary: 100010110
Octal: 426
Hexadecimal: 0x116
Base64: ARY=
One's complement: 65,257 (16-bit)

In other bases

ternary (3) 101022

quaternary (4) 10112

quinary (5) 2103

senary (6) 1142

septenary (7) 545

nonary (9) 338

undecimal (11) 233

duodecimal (12) 1b2

tridecimal (13) 185

tetradecimal (14) 15c

pentadecimal (15) 138

Historical numeral systems

Babylonian (base 60): 𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹
Egyptian hieroglyphic: 𓍢𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓏺𓏺𓏺𓏺𓏺𓏺𓏺𓏺
Greek (Milesian): σοηʹ
Mayan (base 20): 𝋭·𝋲
Chinese: 二百七十八
Chinese (financial): 貳佰柒拾捌

In other modern scripts

Eastern Arabic ٢٧٨ Devanagari २७८ Bengali ২৭৮ Tamil ௨௭௮ Thai ๒๗๘ Tibetan ༢༧༨ Khmer ២៧៨ Lao ໒໗໘ Burmese ၂၇၈

Digit at this position in famous constants

π — Pi (π): Digit 278 = 6
e — Euler's number (e): Digit 278 = 4
φ — Golden ratio (φ): Digit 278 = 8
√2 — Pythagoras's (√2): Digit 278 = 8
ln 2 — Natural log of 2: Digit 278 = 6
γ — Euler-Mascheroni (γ): Digit 278 = 7

Also seen as

Goldbach decomposition

Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 278, here are decompositions:

7 + 271 = 278
37 + 241 = 278
67 + 211 = 278
79 + 199 = 278
97 + 181 = 278
127 + 151 = 278
139 + 139 = 278

Unicode codepoint

Latin Capital Letter E With Dot Above

U+0116

Uppercase letter (Lu)

UTF-8 encoding: C4 96 (2 bytes).

Lookup U+0116 on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#000116

RGB(0, 1, 22)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.1.22.

Address: 0.0.1.22
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.1.22

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