21,220
21,220 is a composite number, even.
Properties
- Parity
- Even
- Digit count
- 5
- Digit sum
- 7
- Digit product
- 0
- Digital root
- 7
- Palindrome
- No
- Bit width
- 15 bits
- Reversed
- 2,212
- Recamán's sequence
- a(41,399) = 21,220
- Square (n²)
- 450,288,400
- Cube (n³)
- 9,555,119,848,000
- Divisor count
- 12
- σ(n) — sum of divisors
- 44,604
- φ(n) — Euler's totient
- 8,480
- Sum of prime factors
- 1,070
Primality
Prime factorization: 2 2 × 5 × 1061
Divisors & multiples
Sums & aliquot sequence
Representations
- In words
- twenty-one thousand two hundred twenty
- Ordinal
- 21220th
- Binary
- 101001011100100
- Octal
- 51344
- Hexadecimal
- 0x52E4
- Base64
- UuQ=
- One's complement
- 44,315 (16-bit)
Historical numeral systems
- Babylonian (base 60)
- 𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒌋𒁹𒁹𒁹 𒌋𒌋𒌋𒌋
- Egyptian hieroglyphic
- 𓂍𓂍𓆼𓍢𓍢𓎆𓎆
- Greek (Milesian)
- ͵κασκʹ
- Mayan (base 20)
- 𝋢·𝋭·𝋡·𝋠
- Chinese
- 二萬一千二百二十
- Chinese (financial)
- 貳萬壹仟貳佰貳拾
Digit at this position in famous constants
- π — Pi (π)
- Digit 21,220 = 4
- e — Euler's number (e)
- Digit 21,220 = 7
- φ — Golden ratio (φ)
- Digit 21,220 = 9
- √2 — Pythagoras's (√2)
- Digit 21,220 = 3
- ln 2 — Natural log of 2
- Digit 21,220 = 3
- γ — Euler-Mascheroni (γ)
- Digit 21,220 = 4
Also seen as
Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 21220, here are decompositions:
- 29 + 21191 = 21220
- 41 + 21179 = 21220
- 71 + 21149 = 21220
- 113 + 21107 = 21220
- 131 + 21089 = 21220
- 197 + 21023 = 21220
- 239 + 20981 = 21220
- 257 + 20963 = 21220
Showing the first eight; more decompositions exist.
UTF-8 encoding: E5 8B A4 (3 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.0.82.228.
- Address
- 0.0.82.228
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.82.228
Unspecified address (0.0.0.0/8) — "this network" placeholder.
The digit sequence 21220 first appears in π at position 77,693 of the decimal expansion (the 77,693ordinal-suffix:rd 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.