21,940
21,940 is a composite number, even.
Properties
- Parity
- Even
- Digit count
- 5
- Digit sum
- 16
- Digit product
- 0
- Digital root
- 7
- Palindrome
- No
- Bit width
- 15 bits
- Reversed
- 4,912
- Recamán's sequence
- a(167,883) = 21,940
- Square (n²)
- 481,363,600
- Cube (n³)
- 10,561,117,384,000
- Divisor count
- 12
- σ(n) — sum of divisors
- 46,116
- φ(n) — Euler's totient
- 8,768
- Sum of prime factors
- 1,106
Primality
Prime factorization: 2 2 × 5 × 1097
Divisors & multiples
Sums & aliquot sequence
Representations
- In words
- twenty-one thousand nine hundred forty
- Ordinal
- 21940th
- Binary
- 101010110110100
- Octal
- 52664
- Hexadecimal
- 0x55B4
- Base64
- VbQ=
- One's complement
- 43,595 (16-bit)
Historical numeral systems
- Babylonian (base 60)
- 𒁹𒁹𒁹𒁹𒁹𒁹 𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋
- Egyptian hieroglyphic
- 𓂍𓂍𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓎆
- Greek (Milesian)
- ͵καϡμʹ
- Mayan (base 20)
- 𝋢·𝋮·𝋱·𝋠
- Chinese
- 二萬一千九百四十
- Chinese (financial)
- 貳萬壹仟玖佰肆拾
Digit at this position in famous constants
- π — Pi (π)
- Digit 21,940 = 5
- e — Euler's number (e)
- Digit 21,940 = 6
- φ — Golden ratio (φ)
- Digit 21,940 = 3
- √2 — Pythagoras's (√2)
- Digit 21,940 = 1
- ln 2 — Natural log of 2
- Digit 21,940 = 6
- γ — Euler-Mascheroni (γ)
- Digit 21,940 = 2
Also seen as
Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 21940, here are decompositions:
- 3 + 21937 = 21940
- 11 + 21929 = 21940
- 29 + 21911 = 21940
- 47 + 21893 = 21940
- 59 + 21881 = 21940
- 89 + 21851 = 21940
- 101 + 21839 = 21940
- 137 + 21803 = 21940
Showing the first eight; more decompositions exist.
UTF-8 encoding: E5 96 B4 (3 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.0.85.180.
- Address
- 0.0.85.180
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.85.180
Unspecified address (0.0.0.0/8) — "this network" placeholder.
This passes the ABA routing number checksum and matches the Federal Reserve numbering scheme.
Banks operate many routing numbers per state and division; an unmatched checksum-valid number can still be a real RTN at a smaller institution.
The digit sequence 21940 first appears in π at position 80,428 of the decimal expansion (the 80,428ordinal-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.