18,021
18,021 is a composite number, odd.
18,021 (eighteen thousand twenty-one) is an odd 5-digit number. It is a composite number with 4 divisors, and factors as 3 × 6,007. Written other ways, in hexadecimal, 0x4665.
Interestingness
Properties
- Parity
- Odd
- Digit count
- 5
- Digit sum
- 12
- Digit product
- 0
- Digital root
- 3
- Palindrome
- No
- Bit width
- 15 bits
- Reversed
- 12,081
- Recamán's sequence
- a(8,118) = 18,021
- Square (n²)
- 324,756,441
- Cube (n³)
- 5,852,435,823,261
- Divisor count
- 4
- σ(n) — sum of divisors
- 24,032
- φ(n) — Euler's totient
- 12,012
- Sum of prime factors
- 6,010
Primality
Prime factorization: 3 × 6007
Divisors & multiples
Sums & aliquot sequence
Continued fraction of √n
√18,021 = [134; (4, 7, 1, 7, 1, 3, 1, 1, 2, 2, 1, 3, 3, 3, 4, 2, 2, 4, 1, 3, 13, 6, 5, 1, …)]
Representations
- In words
- eighteen thousand twenty-one
- Ordinal
- 18021st
- Binary
- 100011001100101
- Octal
- 43145
- Hexadecimal
- 0x4665
- Base64
- RmU=
- One's complement
- 47,514 (16-bit)
- Scientific notation
- 1.8021 × 10⁴
- As a duration
- 18,021 s = 5 hours, 21 seconds
As an angle
Historical numeral systems
- Babylonian (base 60)
- 𒁹𒁹𒁹𒁹𒁹 · 𒌋𒌋𒁹
- Egyptian hieroglyphic
- 𓂍𓆼𓆼𓆼𓆼𓆼𓆼𓆼𓆼𓎆𓎆𓏺
- Greek (Milesian)
- ͵ιηκαʹ
- Mayan (base 20)
- 𝋢·𝋥·𝋡·𝋡
- Chinese
- 一萬八千零二十一
- Chinese (financial)
- 壹萬捌仟零貳拾壹
Digit at this position in famous constants
- π — Pi (π)
- Digit 18,021 = 5
- e — Euler's number (e)
- Digit 18,021 = 7
- φ — Golden ratio (φ)
- Digit 18,021 = 5
- √2 — Pythagoras's (√2)
- Digit 18,021 = 6
- ln 2 — Natural log of 2
- Digit 18,021 = 0
- γ — Euler-Mascheroni (γ)
- Digit 18,021 = 6
Also seen as
UTF-8 encoding: E4 99 A5 (3 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.0.70.101.
- Address
- 0.0.70.101
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.70.101
Unspecified address (0.0.0.0/8) — "this network" placeholder.
Heard as a frequency, 18,021 Hz is closest to:
- Concert pitch (A4 = 440 Hz): C♯10 (17739.7 Hz, +27¢)
- Scientific pitch (C4 = 256 Hz): D10 (18390.4 Hz, -35¢)
- Baroque pitch (A4 = 415 Hz): D10 (17726.7 Hz, +29¢)
The digit sequence 18021 first appears in π at position 31,713 of the decimal expansion (the 31,713ordinal-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.
Related reading
- Babylonian numerals — The base-60 cuneiform system that gave us 60 minutes, 60 seconds, and 360°.