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Number

81,013

81,013 is a prime, odd.

Arithmetic Number Cousin Prime Deficient Number Evil Number Prime Pythagorean Prime Recamán's Sequence Sexy Prime Squarefree

Properties

Parity
Odd
Digit count
5
Digit sum
13
Digit product
0
Digital root
4
Palindrome
No
Bit width
17 bits
Reversed
31,018
Recamán's sequence
a(272,346) = 81,013
Square (n²)
6,563,106,169
Cube (n³)
531,696,920,069,197
Divisor count
2
σ(n) — sum of divisors
81,014
φ(n) — Euler's totient
81,012

Primality

81,013 is prime. It has exactly two divisors: 1 and itself.

Divisors & multiples

All divisors (2)
1 · 81013
Aliquot sum (sum of proper divisors): 1
Factor pairs (a × b = 81,013)
1 × 81013
First multiples
81,013 · 162,026 (double) · 243,039 · 324,052 · 405,065 · 486,078 · 567,091 · 648,104 · 729,117 · 810,130

Sums & aliquot sequence

As a sum of two squares: 183² + 218²
As consecutive integers: 40,506 + 40,507

Representations

In words
eighty-one thousand thirteen
Ordinal
81013th
Binary
10011110001110101
Octal
236165
Hexadecimal
0x13C75
Base64
ATx1
One's complement
4,294,886,282 (32-bit)
In other bases
ternary (3) 11010010111
quaternary (4) 103301311
quinary (5) 10043023
senary (6) 1423021
septenary (7) 455122
nonary (9) 133114
undecimal (11) 55959
duodecimal (12) 3aa71
tridecimal (13) 2ab4a
tetradecimal (14) 21749
pentadecimal (15) 1900d

Historical numeral systems

Babylonian (base 60)
𒌋𒌋𒁹𒁹 𒌋𒌋𒌋 𒌋𒁹𒁹𒁹
Egyptian hieroglyphic
𓂍𓂍𓂍𓂍𓂍𓂍𓂍𓂍𓆼𓎆𓏺𓏺𓏺
Greek (Milesian)
͵παιγʹ
Mayan (base 20)
𝋪·𝋢·𝋪·𝋭
Chinese
八萬一千零一十三
Chinese (financial)
捌萬壹仟零壹拾參
In other modern scripts
Eastern Arabic ٨١٠١٣ Devanagari ८१०१३ Bengali ৮১০১৩ Tamil ௮௧௦௧௩ Thai ๘๑๐๑๓ Tibetan ༨༡༠༡༣ Khmer ៨១០១៣ Lao ໘໑໐໑໓ Burmese ၈၁၀၁၃

Digit at this position in famous constants

π — Pi (π)
Digit 81,013 = 7
e — Euler's number (e)
Digit 81,013 = 8
φ — Golden ratio (φ)
Digit 81,013 = 1
√2 — Pythagoras's (√2)
Digit 81,013 = 9
ln 2 — Natural log of 2
Digit 81,013 = 8
γ — Euler-Mascheroni (γ)
Digit 81,013 = 6

Also seen as

Prime neighborhood

Adjacent primes:

  • Previous prime: 81,001 (gap of 12)
  • Next prime: 81,017 (gap of 4)

Pair status: cousin with 81017.

Unicode codepoint
𓱵
Egyptian Hieroglyph-13C75
U+13C75
Other letter (Lo)

UTF-8 encoding: F0 93 B1 B5 (4 bytes).

Hex color
#013C75
RGB(1, 60, 117)
IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.1.60.117.

Address
0.1.60.117
Class
reserved
IPv4-mapped IPv6
::ffff:0.1.60.117

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

Position in π

The digit sequence 81013 first appears in π at position 27,752 of the decimal expansion (the 27,752ordinal-suffix:nd 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.