21,040
21,040 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
- 4,012
- Recamán's sequence
- a(41,759) = 21,040
- Square (n²)
- 442,681,600
- Cube (n³)
- 9,314,020,864,000
- Divisor count
- 20
- σ(n) — sum of divisors
- 49,104
- φ(n) — Euler's totient
- 8,384
- Sum of prime factors
- 276
Primality
Prime factorization: 2 4 × 5 × 263
Divisors & multiples
Sums & aliquot sequence
Representations
- In words
- twenty-one thousand forty
- Ordinal
- 21040th
- Binary
- 101001000110000
- Octal
- 51060
- Hexadecimal
- 0x5230
- Base64
- UjA=
- One's complement
- 44,495 (16-bit)
Historical numeral systems
- Babylonian (base 60)
- 𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒌋 𒌋𒌋𒌋𒌋
- Egyptian hieroglyphic
- 𓂍𓂍𓆼𓎆𓎆𓎆𓎆
- Greek (Milesian)
- ͵καμʹ
- Mayan (base 20)
- 𝋢·𝋬·𝋬·𝋠
- Chinese
- 二萬一千零四十
- Chinese (financial)
- 貳萬壹仟零肆拾
Digit at this position in famous constants
- π — Pi (π)
- Digit 21,040 = 1
- e — Euler's number (e)
- Digit 21,040 = 6
- φ — Golden ratio (φ)
- Digit 21,040 = 5
- √2 — Pythagoras's (√2)
- Digit 21,040 = 6
- ln 2 — Natural log of 2
- Digit 21,040 = 7
- γ — Euler-Mascheroni (γ)
- Digit 21,040 = 3
Also seen as
Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 21040, here are decompositions:
- 17 + 21023 = 21040
- 23 + 21017 = 21040
- 29 + 21011 = 21040
- 59 + 20981 = 21040
- 101 + 20939 = 21040
- 137 + 20903 = 21040
- 167 + 20873 = 21040
- 191 + 20849 = 21040
Showing the first eight; more decompositions exist.
UTF-8 encoding: E5 88 B0 (3 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.0.82.48.
- Address
- 0.0.82.48
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.82.48
Unspecified address (0.0.0.0/8) — "this network" placeholder.
The digit sequence 21040 first appears in π at position 4,773 of the decimal expansion (the 4,773ordinal-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.