21,172
21,172 is a composite number, even.
Properties
- Parity
- Even
- Digit count
- 5
- Digit sum
- 13
- Digit product
- 28
- Digital root
- 4
- Palindrome
- No
- Bit width
- 15 bits
- Reversed
- 27,112
- Recamán's sequence
- a(41,495) = 21,172
- Square (n²)
- 448,253,584
- Cube (n³)
- 9,490,424,880,448
- Divisor count
- 12
- σ(n) — sum of divisors
- 38,080
- φ(n) — Euler's totient
- 10,296
- Sum of prime factors
- 150
Primality
Prime factorization: 2 2 × 67 × 79
Divisors & multiples
Sums & aliquot sequence
Representations
- In words
- twenty-one thousand one hundred seventy-two
- Ordinal
- 21172nd
- Binary
- 101001010110100
- Octal
- 51264
- Hexadecimal
- 0x52B4
- Base64
- UrQ=
- One's complement
- 44,363 (16-bit)
Historical numeral systems
- Babylonian (base 60)
- 𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒌋𒁹𒁹 𒌋𒌋𒌋𒌋𒌋𒁹𒁹
- Egyptian hieroglyphic
- 𓂍𓂍𓆼𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓏺𓏺
- Greek (Milesian)
- ͵καροβʹ
- Mayan (base 20)
- 𝋢·𝋬·𝋲·𝋬
- Chinese
- 二萬一千一百七十二
- Chinese (financial)
- 貳萬壹仟壹佰柒拾貳
Digit at this position in famous constants
- π — Pi (π)
- Digit 21,172 = 9
- e — Euler's number (e)
- Digit 21,172 = 3
- φ — Golden ratio (φ)
- Digit 21,172 = 7
- √2 — Pythagoras's (√2)
- Digit 21,172 = 4
- ln 2 — Natural log of 2
- Digit 21,172 = 9
- γ — Euler-Mascheroni (γ)
- Digit 21,172 = 5
Also seen as
Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 21172, here are decompositions:
- 3 + 21169 = 21172
- 23 + 21149 = 21172
- 29 + 21143 = 21172
- 71 + 21101 = 21172
- 83 + 21089 = 21172
- 113 + 21059 = 21172
- 149 + 21023 = 21172
- 191 + 20981 = 21172
Showing the first eight; more decompositions exist.
UTF-8 encoding: E5 8A B4 (3 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.0.82.180.
- Address
- 0.0.82.180
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.82.180
Unspecified address (0.0.0.0/8) — "this network" placeholder.
The digit sequence 21172 first appears in π at position 41,733 of the decimal expansion (the 41,733ordinal-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.