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Number

13,831

13,831 is a prime, odd.

13,831 (thirteen thousand eight hundred thirty-one) is an odd 5-digit number. It is a prime number — divisible only by 1 and itself. Its digits read the same forwards and backwards, so it is a palindromic number. Written other ways, in hexadecimal, 0x3607.

Arithmetic Number Cube-Free Deficient Number Odious Number Palindrome Palindromic Prime Pernicious Number Prime Recamán's Sequence Squarefree Twin Prime

Interestingness

Properties

Parity
Odd
Digit count
5
Digit sum
16
Digit product
72
Digital root
7
Palindrome
Yes
Bit width
14 bits
Recamán's sequence
a(21,054) = 13,831
Square (n²)
191,296,561
Cube (n³)
2,645,822,735,191
Divisor count
2
σ(n) — sum of divisors
13,832
φ(n) — Euler's totient
13,830

Primality

13,831 is prime. It has exactly two divisors: 1 and itself.

Divisors & multiples

All divisors (2)
1 · 13831
Aliquot sum (sum of proper divisors): 1
Factor pairs (a × b = 13,831)
1 × 13831
First multiples
13,831 · 27,662 (double) · 41,493 · 55,324 · 69,155 · 82,986 · 96,817 · 110,648 · 124,479 · 138,310

Sums & aliquot sequence

As consecutive integers: 6,915 + 6,916

Continued fraction of √n

√13,831 = [117; (1, 1, 1, 1, 6, 1, 77, 1, 1, 6, 1, 1, 1, 1, 1, 25, 1, 1, 20, 1, 6, 1, 7, 1, …)]

Representations

In words
thirteen thousand eight hundred thirty-one
Ordinal
13831st
Binary
11011000000111
Octal
33007
Hexadecimal
0x3607
Base64
Ngc=
One's complement
51,704 (16-bit)
Scientific notation
1.3831 × 10⁴
As a duration
13,831 s = 3 hours, 50 minutes, 31 seconds
In other bases
ternary (3) 200222021
quaternary (4) 3120013
quinary (5) 420311
senary (6) 144011
septenary (7) 55216
nonary (9) 20867
undecimal (11) a434
duodecimal (12) 8007
tridecimal (13) 63ac
tetradecimal (14) 507d
pentadecimal (15) 4171

As an angle

13,831° = 38 × 360° + 151°
151° ≈ 2.635 rad
Compass bearing: SSE (south-southeast)

Historical numeral systems

Babylonian (base 60)
𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒌋 𒌋𒌋𒌋𒁹
Egyptian hieroglyphic
𓂍𓆼𓆼𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓏺
Greek (Milesian)
͵ιγωλαʹ
Mayan (base 20)
𝋡·𝋮·𝋫·𝋫
Chinese
一萬三千八百三十一
Chinese (financial)
壹萬參仟捌佰參拾壹
In other modern scripts
Eastern Arabic ١٣٨٣١ Devanagari १३८३१ Bengali ১৩৮৩১ Tamil ௧௩௮௩௧ Thai ๑๓๘๓๑ Tibetan ༡༣༨༣༡ Khmer ១៣៨៣១ Lao ໑໓໘໓໑ Burmese ၁၃၈၃၁

Digit at this position in famous constants

π — Pi (π)
Digit 13,831 = 5
e — Euler's number (e)
Digit 13,831 = 7
φ — Golden ratio (φ)
Digit 13,831 = 1
√2 — Pythagoras's (√2)
Digit 13,831 = 2
ln 2 — Natural log of 2
Digit 13,831 = 2
γ — Euler-Mascheroni (γ)
Digit 13,831 = 1

Also seen as

Prime neighborhood

Adjacent primes:

  • Previous prime: 13,829 (gap of 2)
  • Next prime: 13,841 (gap of 10)

Pair status: twin with 13829.

Unicode codepoint
CJK Unified Ideograph-3607
U+3607
Other letter (Lo)

UTF-8 encoding: E3 98 87 (3 bytes).

Hex color
#003607
RGB(0, 54, 7)
IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.54.7.

Address
0.0.54.7
Class
reserved
IPv4-mapped IPv6
::ffff:0.0.54.7

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

Musical pitch

Heard as a frequency, 13,831 Hz is closest to:

  • Concert pitch (A4 = 440 Hz): A9 (14080 Hz, -31¢)
  • Scientific pitch (C4 = 256 Hz): A9 (13777.2 Hz, +7¢)
  • Baroque pitch (A4 = 415 Hz): A♯9 (14069.7 Hz, -30¢)
Position in π

The digit sequence 13831 first appears in π at position 11,000 of the decimal expansion (the 11,000ordinal-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.

Related reading

  • Prime numbers — The building blocks of arithmetic: what primes are, why they matter, and how we find them.
  • Egyptian hieroglyphic numerals — Seven hieroglyphs for every power of ten, from a single stroke to a million.