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Number

81,421

81,421 is a prime, odd.

Arithmetic Number Deficient Number Happy Number Odious Number Prime Pythagorean Prime Recamán's Sequence Squarefree

Properties

Parity
Odd
Digit count
5
Digit sum
16
Digit product
64
Digital root
7
Palindrome
No
Bit width
17 bits
Reversed
12,418
Recamán's sequence
a(271,530) = 81,421
Square (n²)
6,629,379,241
Cube (n³)
539,770,687,181,461
Divisor count
2
σ(n) — sum of divisors
81,422
φ(n) — Euler's totient
81,420

Primality

81,421 is prime. It has exactly two divisors: 1 and itself.

Divisors & multiples

All divisors (2)
1 · 81421
Aliquot sum (sum of proper divisors): 1
Factor pairs (a × b = 81,421)
1 × 81421
First multiples
81,421 · 162,842 (double) · 244,263 · 325,684 · 407,105 · 488,526 · 569,947 · 651,368 · 732,789 · 814,210

Sums & aliquot sequence

As a sum of two squares: 14² + 285²
As consecutive integers: 40,710 + 40,711

Representations

In words
eighty-one thousand four hundred twenty-one
Ordinal
81421st
Binary
10011111000001101
Octal
237015
Hexadecimal
0x13E0D
Base64
AT4N
One's complement
4,294,885,874 (32-bit)
In other bases
ternary (3) 11010200121
quaternary (4) 103320031
quinary (5) 10101141
senary (6) 1424541
septenary (7) 456244
nonary (9) 133617
undecimal (11) 5619a
duodecimal (12) 3b151
tridecimal (13) 2b0a2
tetradecimal (14) 2195b
pentadecimal (15) 191d1

Historical numeral systems

Babylonian (base 60)
𒌋𒌋𒁹𒁹 𒌋𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹𒁹 𒁹
Egyptian hieroglyphic
𓂍𓂍𓂍𓂍𓂍𓂍𓂍𓂍𓆼𓍢𓍢𓍢𓍢𓎆𓎆𓏺
Greek (Milesian)
͵παυκαʹ
Mayan (base 20)
𝋪·𝋣·𝋫·𝋡
Chinese
八萬一千四百二十一
Chinese (financial)
捌萬壹仟肆佰貳拾壹
In other modern scripts
Eastern Arabic ٨١٤٢١ Devanagari ८१४२१ Bengali ৮১৪২১ Tamil ௮௧௪௨௧ Thai ๘๑๔๒๑ Tibetan ༨༡༤༢༡ Khmer ៨១៤២១ Lao ໘໑໔໒໑ Burmese ၈၁၄၂၁

Digit at this position in famous constants

π — Pi (π)
Digit 81,421 = 1
e — Euler's number (e)
Digit 81,421 = 6
φ — Golden ratio (φ)
Digit 81,421 = 7
√2 — Pythagoras's (√2)
Digit 81,421 = 7
ln 2 — Natural log of 2
Digit 81,421 = 8
γ — Euler-Mascheroni (γ)
Digit 81,421 = 0

Also seen as

Prime neighborhood

Adjacent primes:

  • Previous prime: 81,409 (gap of 12)
  • Next prime: 81,439 (gap of 18)
Unicode codepoint
𓸍
Egyptian Hieroglyph-13E0D
U+13E0D
Other letter (Lo)

UTF-8 encoding: F0 93 B8 8D (4 bytes).

Hex color
#013E0D
RGB(1, 62, 13)
IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.1.62.13.

Address
0.1.62.13
Class
reserved
IPv4-mapped IPv6
::ffff:0.1.62.13

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

Position in π

The digit sequence 81421 first appears in π at position 62,414 of the decimal expansion (the 62,414ordinal-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.