Number

18,013

18,013 is a prime, odd.

18,013 (eighteen thousand thirteen) is an odd 5-digit number. It is a prime number — divisible only by 1 and itself. Written other ways, in hexadecimal, 0x465D.

Arithmetic Number Cube-Free Deficient Number Emirp Evil Number Prime Pythagorean Prime Recamán's Sequence Squarefree

Interestingness

★ ★ ★ ★ ☆

7 notable facts · grade B

18,001 18,002 18,003 18,004 18,005 18,006 18,007 18,008 18,009 18,010 18,011 18,012 18,013 18,014 18,015 18,016 18,017 18,018 18,019 18,020 18,021 18,022 18,023 18,024 18,025

less more

Properties

Parity: Odd
Digit count: 5
Digit sum: 13
Digit product: 0
Digital root: 4
Palindrome: No
Bit width: 15 bits
Reversed: 31,081
Recamán's sequence: a(8,134) = 18,013
Square (n²): 324,468,169
Cube (n³): 5,844,645,128,197
Divisor count: 2
σ(n) — sum of divisors: 18,014
φ(n) — Euler's totient: 18,012

Primality

18,013 is prime. It has exactly two divisors: 1 and itself.

Divisors & multiples

All divisors (2)

1 · 18013

Aliquot sum (sum of proper divisors): 1

Factor pairs (a × b = 18,013)

1 × 18013

First multiples

18,013 · 36,026 (double) · 54,039 · 72,052 · 90,065 · 108,078 · 126,091 · 144,104 · 162,117 · 180,130

Sums & aliquot sequence

As a sum of two squares: 18² + 133²

As consecutive integers: 9,006 + 9,007

Continued fraction of √n

√18,013 = [134; (4, 1, 2, 2, 1, 1, 8, 14, 89, 2, 2, 9, 5, 2, 1, 2, 4, 2, 1, 29, 7, 2, 2, 1, …)]

Representations

In words: eighteen thousand thirteen
Ordinal: 18013th
Binary: 100011001011101
Octal: 43135
Hexadecimal: 0x465D
Base64: Rl0=
One's complement: 47,522 (16-bit)
Scientific notation: 1.8013 × 10⁴
As a duration: 18,013 s = 5 hours, 13 seconds

In other bases

ternary (3) 220201011

quaternary (4) 10121131

quinary (5) 1034023

senary (6) 215221

septenary (7) 103342

nonary (9) 26634

undecimal (11) 12596

duodecimal (12) a511

tridecimal (13) 8278

tetradecimal (14) 67c9

pentadecimal (15) 550d

As an angle

18,013° = 50 × 360° + 13°

13° ≈ 0.227 rad

Compass bearing: NNE (north-northeast)

Why does a circle have 360 degrees? →

Historical numeral systems

Babylonian (base 60): 𒁹𒁹𒁹𒁹𒁹 · 𒌋𒁹𒁹𒁹
Egyptian hieroglyphic: 𓂍𓆼𓆼𓆼𓆼𓆼𓆼𓆼𓆼𓎆𓏺𓏺𓏺
Greek (Milesian): ͵ιηιγʹ
Mayan (base 20): 𝋢·𝋥·𝋠·𝋭
Chinese: 一萬八千零一十三
Chinese (financial): 壹萬捌仟零壹拾參

In other modern scripts

Eastern Arabic ١٨٠١٣ Devanagari १८०१३ Bengali ১৮০১৩ Tamil ௧௮௦௧௩ Thai ๑๘๐๑๓ Tibetan ༡༨༠༡༣ Khmer ១៨០១៣ Lao ໑໘໐໑໓ Burmese ၁၈၀၁၃

Digit at this position in famous constants

π — Pi (π): Digit 18,013 = 6
e — Euler's number (e): Digit 18,013 = 6
φ — Golden ratio (φ): Digit 18,013 = 1
√2 — Pythagoras's (√2): Digit 18,013 = 0
ln 2 — Natural log of 2: Digit 18,013 = 2
γ — Euler-Mascheroni (γ): Digit 18,013 = 0

Also seen as

Prime neighborhood

Adjacent primes:

Previous prime: 17,989 (gap of 24)
Next prime: 18,041 (gap of 28)

Unicode codepoint

䙝

CJK Unified Ideograph-465D

U+465D

Other letter (Lo)

UTF-8 encoding: E4 99 9D (3 bytes).

Lookup U+465D on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#00465D

RGB(0, 70, 93)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.70.93.

Address: 0.0.70.93
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.70.93

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

Musical pitch

Heard as a frequency, 18,013 Hz is closest to:

Concert pitch (A4 = 440 Hz): C♯10 (17739.7 Hz, +26¢)
Scientific pitch (C4 = 256 Hz): D10 (18390.4 Hz, -36¢)
Baroque pitch (A4 = 415 Hz): D10 (17726.7 Hz, +28¢)

Position in π

The digit sequence 18013 first appears in π at position 207,823 of the decimal expansion (the 207,823ordinal-suffix:rd 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.

Look up 18013 on Pi Search ↗