Number

918

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

918 (nine hundred eighteen) is an even 3-digit number. It is a composite number with 16 divisors, and factors as 2 × 3³ × 17. Its proper divisors sum to 1,242, more than the number itself, making it an abundant number. Written other ways, in Roman numerals it is CMXVIII and in binary, 1110010110.

Abundant Number Arithmetic Number Evil Number Flippable Harshad / Niven Practical Number Recamán's Sequence Self Number Semiperfect Number Year

Interestingness

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7 notable facts · grade B

906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930

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Historical context — 918 AD

Calendar year

Year 918 (CMXVIII) was a common year starting on Thursday of the Julian calendar.

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

Historical context — 918 BC

Decade

The 910s BC is a decade that lasted from 919 BC to 910 BC.

Excerpt from Wikipedia (en) ↗ · Licensed CC BY-SA 4.0 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: Saturday
January 1, 918
Ended on: Saturday
December 31, 918
Friday the 13ths: 1
One Friday the 13th this year.
Decade: 910s
910–919
Century: 10th century
901–1000
Millennium: 1st millennium
1–1000
Years ago: 1,108
1108 years before 2026.

In other calendars

Hebrew: 4678 / 4679 AM
Rosh Hashanah falls in September/October.
Islamic Hijri: 305 / 306 AH
Lunar calendar; year spans differ from Gregorian.
Chinese: Year of the zodiac:Earth zodiac:Tiger
Sexagenary cycle position 15 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era: 1461 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Persian Solar Hijri: 296 / 297 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
Ethiopian: 910 / 911 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): 840 / 839 Saka
Indian national calendar; year starts in March.

Properties

Parity: Even
Digit count: 3
Digit sum: 18
Digit product: 72
Digital root: 9
Palindrome: No
Bit width: 10 bits
Reversed: 819
Flips to (rotate 180°): 816
Recamán's sequence: a(587) = 918
Square (n²): 842,724
Cube (n³): 773,620,632
Divisor count: 16
σ(n) — sum of divisors: 2,160
φ(n) — Euler's totient: 288
Sum of prime factors: 28

Primality

Prime factorization: 2 × 3 ³ × 17

Nearest primes: 911 (−7) · 919 (+1)

Divisors & multiples

All divisors (16)

1 · 2 · 3 · 6 · 9 · 17 · 18 · 27 · 34 · 51 · 54 · 102 · 153 · 306 · 459 (half) · 918

Aliquot sum (sum of proper divisors): 1,242

Factor pairs (a × b = 918)

1 × 918

2 × 459

3 × 306

6 × 153

9 × 102

17 × 54

18 × 51

27 × 34

First multiples

918 · 1,836 (double) · 2,754 · 3,672 · 4,590 · 5,508 · 6,426 · 7,344 · 8,262 · 9,180

Sums & aliquot sequence

As consecutive integers: 305 + 306 + 307 228 + 229 + 230 + 231 98 + 99 + … + 106 71 + 72 + … + 82

Aliquot sequence: 918 → 1,242 → 1,638 → 2,730 → 5,334 → 6,954 → 7,926 → 7,938 → 12,753 → 7,267 → 785 → 163 → 1 → 0 — terminates at zero

Continued fraction of √n

√918 = [30; (3, 2, 1, 6, 30, 6, 1, 2, 3, 60)]

Period length 10 — the block in parentheses repeats forever.

Representations

In words: nine hundred eighteen
Ordinal: 918th
Roman numeral: CMXVIII
Binary: 1110010110
Octal: 1626
Hexadecimal: 0x396
Base64: A5Y=
One's complement: 64,617 (16-bit)
Scientific notation: 9.18 × 10²
As a duration: 918 s = 15 minutes, 18 seconds

In other bases

ternary (3) 1021000

quaternary (4) 32112

quinary (5) 12133

senary (6) 4130

septenary (7) 2451

nonary (9) 1230

undecimal (11) 765

duodecimal (12) 646

tridecimal (13) 558

tetradecimal (14) 498

pentadecimal (15) 413

Palindromic in base 12

As an angle

918° = 2 × 360° + 198°

198° ≈ 3.456 rad

Compass bearing: SSW (south-southwest)

Why does a circle have 360 degrees? →

Historical numeral systems

Babylonian (base 60): 𒌋𒁹𒁹𒁹𒁹𒁹 𒌋𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹
Egyptian hieroglyphic: 𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓏺𓏺𓏺𓏺𓏺𓏺𓏺𓏺
Greek (Milesian): ϡιηʹ
Mayan (base 20): 𝋢·𝋥·𝋲
Chinese: 九百一十八
Chinese (financial): 玖佰壹拾捌

In other modern scripts

Eastern Arabic ٩١٨ Devanagari ९१८ Bengali ৯১৮ Tamil ௯௧௮ Thai ๙๑๘ Tibetan ༩༡༨ Khmer ៩១៨ Lao ໙໑໘ Burmese ၉၁၈

Digit at this position in famous constants

π — Pi (π): Digit 918 = 6
e — Euler's number (e): Digit 918 = 9
φ — Golden ratio (φ): Digit 918 = 2
√2 — Pythagoras's (√2): Digit 918 = 4
ln 2 — Natural log of 2: Digit 918 = 8
γ — Euler-Mascheroni (γ): Digit 918 = 4

Also seen as

Goldbach decomposition

Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 918, here are decompositions:

7 + 911 = 918
11 + 907 = 918
31 + 887 = 918
37 + 881 = 918
41 + 877 = 918
59 + 859 = 918
61 + 857 = 918
79 + 839 = 918

Showing the first eight; more decompositions exist.

Unicode codepoint

Greek Capital Letter Zeta

U+0396

Uppercase letter (Lu)

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

Lookup U+0396 on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#000396

RGB(0, 3, 150)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.3.150.

Address: 0.0.3.150
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.3.150

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

NANP area code 918

The number 918 is an active NANP area code (North American Numbering Plan).

Primary area: Tulsa
Region: Oklahoma
Country: United States

Most NANP area codes have multiple overlays in dense regions; the primary area listed is the historic/largest population center for this code.

Look up area code 918 ↗

Musical pitch

Heard as a frequency, 918 Hz is closest to:

Concert pitch (A4 = 440 Hz): A♯5 (932.3 Hz, -27¢)
Scientific pitch (C4 = 256 Hz): A♯5 (912.3 Hz, +11¢)
Baroque pitch (A4 = 415 Hz): B5 (931.6 Hz, -26¢)