21,942
21,942 is a composite number, even.
Properties
- Parity
- Even
- Digit count
- 5
- Digit sum
- 18
- Digit product
- 144
- Digital root
- 9
- Palindrome
- No
- Bit width
- 15 bits
- Reversed
- 24,912
- Recamán's sequence
- a(167,879) = 21,942
- Square (n²)
- 481,451,364
- Cube (n³)
- 10,564,005,828,888
- Divisor count
- 24
- σ(n) — sum of divisors
- 50,544
- φ(n) — Euler's totient
- 6,864
- Sum of prime factors
- 84
Primality
Prime factorization: 2 × 3 2 × 23 × 53
Divisors & multiples
Sums & aliquot sequence
Representations
- In words
- twenty-one thousand nine hundred forty-two
- Ordinal
- 21942nd
- Binary
- 101010110110110
- Octal
- 52666
- Hexadecimal
- 0x55B6
- Base64
- VbY=
- One's complement
- 43,593 (16-bit)
Historical numeral systems
- Babylonian (base 60)
- 𒁹𒁹𒁹𒁹𒁹𒁹 𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒁹𒁹
- Egyptian hieroglyphic
- 𓂍𓂍𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓎆𓏺𓏺
- Greek (Milesian)
- ͵καϡμβʹ
- Mayan (base 20)
- 𝋢·𝋮·𝋱·𝋢
- Chinese
- 二萬一千九百四十二
- Chinese (financial)
- 貳萬壹仟玖佰肆拾貳
Digit at this position in famous constants
- π — Pi (π)
- Digit 21,942 = 7
- e — Euler's number (e)
- Digit 21,942 = 9
- φ — Golden ratio (φ)
- Digit 21,942 = 8
- √2 — Pythagoras's (√2)
- Digit 21,942 = 2
- ln 2 — Natural log of 2
- Digit 21,942 = 3
- γ — Euler-Mascheroni (γ)
- Digit 21,942 = 9
Also seen as
Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 21942, here are decompositions:
- 5 + 21937 = 21942
- 13 + 21929 = 21942
- 31 + 21911 = 21942
- 61 + 21881 = 21942
- 71 + 21871 = 21942
- 79 + 21863 = 21942
- 83 + 21859 = 21942
- 101 + 21841 = 21942
Showing the first eight; more decompositions exist.
UTF-8 encoding: E5 96 B6 (3 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.0.85.182.
- Address
- 0.0.85.182
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.85.182
Unspecified address (0.0.0.0/8) — "this network" placeholder.
The digit sequence 21942 first appears in π at position 37,122 of the decimal expansion (the 37,122ordinal-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.