Live analysis

21,003

21,003 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.).

21,003 (twenty-one thousand three) is an odd 5-digit number. It is a composite number with 4 divisors, and factors as 3 × 7,001. Written other ways, in hexadecimal, 0x520B.

Arithmetic Number Cube-Free Deficient Number Evil Number Recamán's Sequence Semiprime Squarefree

Interestingness

★ ★ ★ ☆ ☆

5 notable facts · grade C

20,991 20,992 20,993 20,994 20,995 20,996 20,997 20,998 20,999 21,000 21,001 21,002 21,003 21,004 21,005 21,006 21,007 21,008 21,009 21,010 21,011 21,012 21,013 21,014 21,015

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Properties

Parity: Odd
Digit count: 5
Digit sum: 6
Digit product: 0
Digital root: 6
Palindrome: No
Bit width: 15 bits
Reversed: 30,012
Recamán's sequence: a(41,833) = 21,003
Square (n²): 441,126,009
Cube (n³): 9,264,969,567,027
Divisor count: 4
σ(n) — sum of divisors: 28,008
φ(n) — Euler's totient: 14,000
Sum of prime factors: 7,004

Primality

Prime factorization: 3 × 7001

Nearest primes: 21,001 (−2) · 21,011 (+8)

Divisors & multiples

All divisors (4)

1 · 3 · 7001 · 21003

Aliquot sum (sum of proper divisors): 7,005

Factor pairs (a × b = 21,003)

1 × 21003

3 × 7001

First multiples

21,003 · 42,006 (double) · 63,009 · 84,012 · 105,015 · 126,018 · 147,021 · 168,024 · 189,027 · 210,030

Sums & aliquot sequence

As consecutive integers: 10,501 + 10,502 7,000 + 7,001 + 7,002 3,498 + 3,499 + 3,500 + 3,501 + 3,502 + 3,503

Aliquot sequence: 21,003 → 7,005 → 4,227 → 1,413 → 641 → 1 → 0 — terminates at zero

Continued fraction of √n

√21,003 = [144; (1, 12, 5, 1, 1, 1, 1, 5, 1, 2, 3, 1, 2, 1, 2, 1, 1, 2, 12, 4, 1, 2, 25, 1, …)]

Period length 50 — the block in parentheses repeats forever.

Representations

In words: twenty-one thousand three
Ordinal: 21003rd
Binary: 101001000001011
Octal: 51013
Hexadecimal: 0x520B
Base64: Ugs=
One's complement: 44,532 (16-bit)
Scientific notation: 2.1003 × 10⁴
As a duration: 21,003 s = 5 hours, 50 minutes, 3 seconds

In other bases

ternary (3) 1001210220

quaternary (4) 11020023

quinary (5) 1133003

senary (6) 241123

septenary (7) 115143

nonary (9) 31726

undecimal (11) 14864

duodecimal (12) 101a3

tridecimal (13) 9738

tetradecimal (14) 7923

pentadecimal (15) 6353

As an angle

21,003° = 58 × 360° + 123°

123° ≈ 2.147 rad

Compass bearing: ESE (east-southeast)

Why does a circle have 360 degrees? →

Historical numeral systems

Babylonian (base 60): 𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒌋 𒁹𒁹𒁹
Egyptian hieroglyphic: 𓂍𓂍𓆼𓏺𓏺𓏺
Greek (Milesian): ͵καγʹ
Mayan (base 20): 𝋢·𝋬·𝋪·𝋣
Chinese: 二萬一千零三
Chinese (financial): 貳萬壹仟零參

In other modern scripts

Eastern Arabic ٢١٠٠٣ Devanagari २१००३ Bengali ২১০০৩ Tamil ௨௧௦௦௩ Thai ๒๑๐๐๓ Tibetan ༢༡༠༠༣ Khmer ២១០០៣ Lao ໒໑໐໐໓ Burmese ၂၁၀၀၃

Digit at this position in famous constants

π — Pi (π): Digit 21,003 = 4
e — Euler's number (e): Digit 21,003 = 8
φ — Golden ratio (φ): Digit 21,003 = 4
√2 — Pythagoras's (√2): Digit 21,003 = 3
ln 2 — Natural log of 2: Digit 21,003 = 7
γ — Euler-Mascheroni (γ): Digit 21,003 = 1

Also seen as

Unicode codepoint

刋

CJK Unified Ideograph-520B

U+520B

Other letter (Lo)

UTF-8 encoding: E5 88 8B (3 bytes).

Lookup U+520B on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#00520B

RGB(0, 82, 11)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.82.11.

Address: 0.0.82.11
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.82.11

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

Position in π

The digit sequence 21003 first appears in π at position 12,290 of the decimal expansion (the 12,290ordinal-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.

Look up 21003 on Pi Search ↗