18,421
18,421 is a composite number, odd.
18,421 (eighteen thousand four hundred twenty-one) is an odd 5-digit number. It is a composite number with 6 divisors, and factors as 13² × 109. Written other ways, in hexadecimal, 0x47F5.
Interestingness
Properties
- Parity
- Odd
- Digit count
- 5
- Digit sum
- 16
- Digit product
- 64
- Digital root
- 7
- Palindrome
- No
- Bit width
- 15 bits
- Reversed
- 12,481
- Recamán's sequence
- a(13,686) = 18,421
- Square (n²)
- 339,333,241
- Cube (n³)
- 6,250,857,632,461
- Divisor count
- 6
- σ(n) — sum of divisors
- 20,130
- φ(n) — Euler's totient
- 16,848
- Sum of prime factors
- 135
Primality
Prime factorization: 13 2 × 109
Divisors & multiples
Sums & aliquot sequence
Continued fraction of √n
√18,421 = [135; (1, 2, 1, 1, 1, 1, 1, 7, 7, 2, 2, 4, 22, 2, 1, 1, 5, 1, 2, 1, 1, 89, 1, 9, …)]
Representations
- In words
- eighteen thousand four hundred twenty-one
- Ordinal
- 18421st
- Binary
- 100011111110101
- Octal
- 43765
- Hexadecimal
- 0x47F5
- Base64
- R/U=
- One's complement
- 47,114 (16-bit)
- Scientific notation
- 1.8421 × 10⁴
- As a duration
- 18,421 s = 5 hours, 7 minutes, 1 second
As an angle
Historical numeral systems
- Babylonian (base 60)
- 𒁹𒁹𒁹𒁹𒁹 𒁹𒁹𒁹𒁹𒁹𒁹𒁹 𒁹
- Egyptian hieroglyphic
- 𓂍𓆼𓆼𓆼𓆼𓆼𓆼𓆼𓆼𓍢𓍢𓍢𓍢𓎆𓎆𓏺
- Greek (Milesian)
- ͵ιηυκαʹ
- Mayan (base 20)
- 𝋢·𝋦·𝋡·𝋡
- Chinese
- 一萬八千四百二十一
- Chinese (financial)
- 壹萬捌仟肆佰貳拾壹
Digit at this position in famous constants
- π — Pi (π)
- Digit 18,421 = 5
- e — Euler's number (e)
- Digit 18,421 = 6
- φ — Golden ratio (φ)
- Digit 18,421 = 2
- √2 — Pythagoras's (√2)
- Digit 18,421 = 8
- ln 2 — Natural log of 2
- Digit 18,421 = 1
- γ — Euler-Mascheroni (γ)
- Digit 18,421 = 2
Also seen as
UTF-8 encoding: E4 9F B5 (3 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.0.71.245.
- Address
- 0.0.71.245
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.71.245
Unspecified address (0.0.0.0/8) — "this network" placeholder.
Heard as a frequency, 18,421 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, -33¢)
The digit sequence 18421 first appears in π at position 358,862 of the decimal expansion (the 358,862ordinal-suffix:nd 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.
Related reading
- Egyptian hieroglyphic numerals — Seven hieroglyphs for every power of ten, from a single stroke to a million.