number.wiki
Live analysis

21,124

21,124 is a composite number, even.

This number doesn't have a permanent NumberWiki page yet — what you see below is computed live. Pages get added to the permanent index when they're notable (years, primes, curated, etc.).
Deficient Number Odious Number Pernicious Number Recamán's Sequence Self Number

Properties

Parity
Even
Digit count
5
Digit sum
10
Digit product
16
Digital root
1
Palindrome
No
Bit width
15 bits
Reversed
42,112
Recamán's sequence
a(41,591) = 21,124
Square (n²)
446,223,376
Cube (n³)
9,426,022,594,624
Divisor count
6
σ(n) — sum of divisors
36,974
φ(n) — Euler's totient
10,560
Sum of prime factors
5,285

Primality

Prime factorization: 2 2 × 5281

Nearest primes: 21,121 (−3) · 21,139 (+15)

Divisors & multiples

All divisors (6)
1 · 2 · 4 · 5281 · 10562 (half) · 21124
Aliquot sum (sum of proper divisors): 15,850
Factor pairs (a × b = 21,124)
1 × 21124
2 × 10562
4 × 5281
First multiples
21,124 · 42,248 (double) · 63,372 · 84,496 · 105,620 · 126,744 · 147,868 · 168,992 · 190,116 · 211,240

Sums & aliquot sequence

As a sum of two squares: 82² + 120²
As consecutive integers: 2,637 + 2,638 + … + 2,644
Aliquot sequence: 21,124 15,850 13,724 11,140 12,296 12,004 9,010 8,486 4,246 2,738 1,483 1 0 — terminates at zero

Representations

In words
twenty-one thousand one hundred twenty-four
Ordinal
21124th
Binary
101001010000100
Octal
51204
Hexadecimal
0x5284
Base64
UoQ=
One's complement
44,411 (16-bit)
In other bases
ternary (3) 1001222101
quaternary (4) 11022010
quinary (5) 1133444
senary (6) 241444
septenary (7) 115405
nonary (9) 31871
undecimal (11) 14964
duodecimal (12) 10284
tridecimal (13) 97cc
tetradecimal (14) 79ac
pentadecimal (15) 63d4

Historical numeral systems

Babylonian (base 60)
𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒌋𒁹𒁹 𒁹𒁹𒁹𒁹
Egyptian hieroglyphic
𓂍𓂍𓆼𓍢𓎆𓎆𓏺𓏺𓏺𓏺
Greek (Milesian)
͵καρκδʹ
Mayan (base 20)
𝋢·𝋬·𝋰·𝋤
Chinese
二萬一千一百二十四
Chinese (financial)
貳萬壹仟壹佰貳拾肆
In other modern scripts
Eastern Arabic ٢١١٢٤ Devanagari २११२४ Bengali ২১১২৪ Tamil ௨௧௧௨௪ Thai ๒๑๑๒๔ Tibetan ༢༡༡༢༤ Khmer ២១១២៤ Lao ໒໑໑໒໔ Burmese ၂၁၁၂၄

Digit at this position in famous constants

π — Pi (π)
Digit 21,124 = 1
e — Euler's number (e)
Digit 21,124 = 9
φ — Golden ratio (φ)
Digit 21,124 = 7
√2 — Pythagoras's (√2)
Digit 21,124 = 3
ln 2 — Natural log of 2
Digit 21,124 = 7
γ — Euler-Mascheroni (γ)
Digit 21,124 = 1

Also seen as

Goldbach decomposition

Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 21124, here are decompositions:

  • 3 + 21121 = 21124
  • 17 + 21107 = 21124
  • 23 + 21101 = 21124
  • 101 + 21023 = 21124
  • 107 + 21017 = 21124
  • 113 + 21011 = 21124
  • 227 + 20897 = 21124
  • 251 + 20873 = 21124

Showing the first eight; more decompositions exist.

Unicode codepoint
CJK Unified Ideograph-5284
U+5284
Other letter (Lo)

UTF-8 encoding: E5 8A 84 (3 bytes).

Hex color
#005284
RGB(0, 82, 132)
IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.82.132.

Address
0.0.82.132
Class
reserved
IPv4-mapped IPv6
::ffff:0.0.82.132

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

Position in π

The digit sequence 21124 first appears in π at position 51,713 of the decimal expansion (the 51,713ordinal-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.