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20,813

20,813 is a composite number, odd.

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.).
Arithmetic Number Deficient Number Odious Number Pernicious Number Recamán's Sequence Semiprime Squarefree

Properties

Parity
Odd
Digit count
5
Digit sum
14
Digit product
0
Digital root
5
Palindrome
No
Bit width
15 bits
Reversed
31,802
Recamán's sequence
a(42,213) = 20,813
Square (n²)
433,180,969
Cube (n³)
9,015,795,507,797
Divisor count
4
σ(n) — sum of divisors
22,428
φ(n) — Euler's totient
19,200
Sum of prime factors
1,614

Primality

Prime factorization: 13 × 1601

Nearest primes: 20,809 (−4) · 20,849 (+36)

Divisors & multiples

All divisors (4)
1 · 13 · 1601 · 20813
Aliquot sum (sum of proper divisors): 1,615
Factor pairs (a × b = 20,813)
1 × 20813
13 × 1601
First multiples
20,813 · 41,626 (double) · 62,439 · 83,252 · 104,065 · 124,878 · 145,691 · 166,504 · 187,317 · 208,130

Sums & aliquot sequence

As a sum of two squares: 77² + 122² = 83² + 118²
As consecutive integers: 10,406 + 10,407 1,595 + 1,596 + … + 1,607 788 + 789 + … + 813
Aliquot sequence: 20,813 1,615 545 115 29 1 0 — terminates at zero

Representations

In words
twenty thousand eight hundred thirteen
Ordinal
20813th
Binary
101000101001101
Octal
50515
Hexadecimal
0x514D
Base64
UU0=
One's complement
44,722 (16-bit)
In other bases
ternary (3) 1001112212
quaternary (4) 11011031
quinary (5) 1131223
senary (6) 240205
septenary (7) 114452
nonary (9) 31485
undecimal (11) 14701
duodecimal (12) 10065
tridecimal (13) 9620
tetradecimal (14) 7829
pentadecimal (15) 6278

Historical numeral systems

Babylonian (base 60)
𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒌋𒁹𒁹𒁹
Egyptian hieroglyphic
𓂍𓂍𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓏺𓏺𓏺
Greek (Milesian)
͵κωιγʹ
Mayan (base 20)
𝋢·𝋬·𝋠·𝋭
Chinese
二萬零八百一十三
Chinese (financial)
貳萬零捌佰壹拾參
In other modern scripts
Eastern Arabic ٢٠٨١٣ Devanagari २०८१३ Bengali ২০৮১৩ Tamil ௨௦௮௧௩ Thai ๒๐๘๑๓ Tibetan ༢༠༨༡༣ Khmer ២០៨១៣ Lao ໒໐໘໑໓ Burmese ၂၀၈၁၃

Digit at this position in famous constants

π — Pi (π)
Digit 20,813 = 5
e — Euler's number (e)
Digit 20,813 = 1
φ — Golden ratio (φ)
Digit 20,813 = 1
√2 — Pythagoras's (√2)
Digit 20,813 = 3
ln 2 — Natural log of 2
Digit 20,813 = 7
γ — Euler-Mascheroni (γ)
Digit 20,813 = 8

Also seen as

Unicode codepoint
CJK Unified Ideograph-514D
U+514D
Other letter (Lo)

UTF-8 encoding: E5 85 8D (3 bytes).

Hex color
#00514D
RGB(0, 81, 77)
IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.81.77.

Address
0.0.81.77
Class
reserved
IPv4-mapped IPv6
::ffff:0.0.81.77

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

Position in π

The digit sequence 20813 first appears in π at position 164,116 of the decimal expansion (the 164,116ordinal-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.