Live analysis

18,420

18,420 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.).

18,420 (eighteen thousand four hundred twenty) is an even 5-digit number. It is a composite number with 24 divisors, and factors as 2² × 3 × 5 × 307. Its proper divisors sum to 33,324, more than the number itself, making it an abundant number. Written other ways, in hexadecimal, 0x47F4.

Abundant Number Arithmetic Number Cube-Free Gapful Number Harshad / Niven Odious Number Recamán's Sequence Self Number Semiperfect Number

Interestingness

★ ★ ★ ★ ☆

7 notable facts · grade B

18,408 18,409 18,410 18,411 18,412 18,413 18,414 18,415 18,416 18,417 18,418 18,419 18,420 18,421 18,422 18,423 18,424 18,425 18,426 18,427 18,428 18,429 18,430 18,431 18,432

less more

Properties

Parity: Even
Digit count: 5
Digit sum: 15
Digit product: 0
Digital root: 6
Palindrome: No
Bit width: 15 bits
Reversed: 2,481
Recamán's sequence: a(8,740) = 18,420
Square (n²): 339,296,400
Cube (n³): 6,249,839,688,000
Divisor count: 24
σ(n) — sum of divisors: 51,744
φ(n) — Euler's totient: 4,896
Sum of prime factors: 319

Primality

Prime factorization: 2 ² × 3 × 5 × 307

Nearest primes: 18,413 (−7) · 18,427 (+7)

Divisors & multiples

All divisors (24)

1 · 2 · 3 · 4 · 5 · 6 · 10 · 12 · 15 · 20 · 30 · 60 · 307 · 614 · 921 · 1228 · 1535 · 1842 · 3070 · 3684 · 4605 · 6140 · 9210 (half) · 18420

Aliquot sum (sum of proper divisors): 33,324

Factor pairs (a × b = 18,420)

1 × 18420

2 × 9210

3 × 6140

4 × 4605

5 × 3684

6 × 3070

10 × 1842

12 × 1535

15 × 1228

20 × 921

30 × 614

60 × 307

First multiples

18,420 · 36,840 (double) · 55,260 · 73,680 · 92,100 · 110,520 · 128,940 · 147,360 · 165,780 · 184,200

Sums & aliquot sequence

As consecutive integers: 6,139 + 6,140 + 6,141 3,682 + 3,683 + 3,684 + 3,685 + 3,686 2,299 + 2,300 + … + 2,306 1,221 + 1,222 + … + 1,235

Aliquot sequence: 18,420 → 33,324 → 44,460 → 108,420 → 220,860 → 467,940 → 963,420 → 1,734,324 → 2,351,436 → 3,355,356 → 4,473,836 → 3,690,964 → 2,768,230 → 2,214,602 → 1,551,958 → 898,562 → 708,154 — unresolved within range

Continued fraction of √n

√18,420 = [135; (1, 2, 1, 1, 2, 1, 4, 1, 1, 1, 1, 16, 2, 1, 3, 1, 12, 1, 3, 1, 2, 16, 1, 1, …)]

Period length 34 — the block in parentheses repeats forever.

Representations

In words: eighteen thousand four hundred twenty
Ordinal: 18420th
Binary: 100011111110100
Octal: 43764
Hexadecimal: 0x47F4
Base64: R/Q=
One's complement: 47,115 (16-bit)
Scientific notation: 1.842 × 10⁴
As a duration: 18,420 s = 5 hours, 7 minutes

In other bases

ternary (3) 221021020

quaternary (4) 10133310

quinary (5) 1042140

senary (6) 221140

septenary (7) 104463

nonary (9) 27236

undecimal (11) 12926

duodecimal (12) a7b0

tridecimal (13) 84cc

tetradecimal (14) 69da

pentadecimal (15) 56d0

As an angle

18,420° = 51 × 360° + 60°

60° ≈ 1.047 rad

Compass bearing: ENE (east-northeast)

Why does a circle have 360 degrees? →

Historical numeral systems

Babylonian (base 60): 𒁹𒁹𒁹𒁹𒁹 𒁹𒁹𒁹𒁹𒁹𒁹𒁹 ·
Egyptian hieroglyphic: 𓂍𓆼𓆼𓆼𓆼𓆼𓆼𓆼𓆼𓍢𓍢𓍢𓍢𓎆𓎆
Greek (Milesian): ͵ιηυκʹ
Mayan (base 20): 𝋢·𝋦·𝋡·𝋠
Chinese: 一萬八千四百二十
Chinese (financial): 壹萬捌仟肆佰貳拾

In other modern scripts

Eastern Arabic ١٨٤٢٠ Devanagari १८४२० Bengali ১৮৪২০ Tamil ௧௮௪௨௦ Thai ๑๘๔๒๐ Tibetan ༡༨༤༢༠ Khmer ១៨៤២០ Lao ໑໘໔໒໐ Burmese ၁၈၄၂၀

Digit at this position in famous constants

π — Pi (π): Digit 18,420 = 3
e — Euler's number (e): Digit 18,420 = 9
φ — Golden ratio (φ): Digit 18,420 = 1
√2 — Pythagoras's (√2): Digit 18,420 = 1
ln 2 — Natural log of 2: Digit 18,420 = 3
γ — Euler-Mascheroni (γ): Digit 18,420 = 6

Also seen as

Goldbach decomposition

Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 18420, here are decompositions:

7 + 18413 = 18420
19 + 18401 = 18420
23 + 18397 = 18420
41 + 18379 = 18420
53 + 18367 = 18420
67 + 18353 = 18420
79 + 18341 = 18420
107 + 18313 = 18420

Showing the first eight; more decompositions exist.

Unicode codepoint

䟴

CJK Unified Ideograph-47F4

U+47F4

Other letter (Lo)

UTF-8 encoding: E4 9F B4 (3 bytes).

Lookup U+47F4 on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#0047F4

RGB(0, 71, 244)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.71.244.

Address: 0.0.71.244
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.71.244

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

Musical pitch

Heard as a frequency, 18,420 Hz is closest to:

Concert pitch (A4 = 440 Hz): D10 (18794.5 Hz, -35¢)
Scientific pitch (C4 = 256 Hz): D10 (18390.4 Hz, +3¢)
Baroque pitch (A4 = 415 Hz): D♯10 (18780.8 Hz, -34¢)

Position in π

The digit sequence 18420 first appears in π at position 59,797 of the decimal expansion (the 59,797ordinal-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 18420 on Pi Search ↗