Number
21,481
21,481 is a prime, odd.
Properties
- Parity
- Odd
- Digit count
- 5
- Digit sum
- 16
- Digit product
- 64
- Digital root
- 7
- Palindrome
- No
- Bit width
- 15 bits
- Reversed
- 18,412
- Recamán's sequence
- a(40,877) = 21,481
- Square (n²)
- 461,433,361
- Cube (n³)
- 9,912,050,027,641
- Divisor count
- 2
- σ(n) — sum of divisors
- 21,482
- φ(n) — Euler's totient
- 21,480
Primality
21,481 is prime. It has exactly two divisors: 1 and itself.
Divisors & multiples
Aliquot sum (sum of proper divisors):
1
First multiples
21,481
·
42,962
(double)
·
64,443
·
85,924
·
107,405
·
128,886
·
150,367
·
171,848
·
193,329
·
214,810
Sums & aliquot sequence
As a sum of two squares:
40² + 141²
As consecutive integers:
10,740 + 10,741
Representations
- In words
- twenty-one thousand four hundred eighty-one
- Ordinal
- 21481st
- Binary
- 101001111101001
- Octal
- 51751
- Hexadecimal
- 0x53E9
- Base64
- U+k=
- One's complement
- 44,054 (16-bit)
In other bases
ternary (3)
1002110121
quaternary (4)
11033221
quinary (5)
1141411
senary (6)
243241
septenary (7)
116425
nonary (9)
32417
undecimal (11)
15159
duodecimal (12)
10521
tridecimal (13)
9a15
tetradecimal (14)
7b85
pentadecimal (15)
6571
Historical numeral systems
- Babylonian (base 60)
- 𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹 𒁹
- Egyptian hieroglyphic
- 𓂍𓂍𓆼𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓏺
- Greek (Milesian)
- ͵καυπαʹ
- Mayan (base 20)
- 𝋢·𝋭·𝋮·𝋡
- Chinese
- 二萬一千四百八十一
- Chinese (financial)
- 貳萬壹仟肆佰捌拾壹
In other modern scripts
Eastern Arabic
٢١٤٨١
Devanagari
२१४८१
Bengali
২১৪৮১
Tamil
௨௧௪௮௧
Thai
๒๑๔๘๑
Tibetan
༢༡༤༨༡
Khmer
២១៤៨១
Lao
໒໑໔໘໑
Burmese
၂၁၄၈၁
Digit at this position in famous constants
- π — Pi (π)
- Digit 21,481 = 1
- e — Euler's number (e)
- Digit 21,481 = 0
- φ — Golden ratio (φ)
- Digit 21,481 = 4
- √2 — Pythagoras's (√2)
- Digit 21,481 = 8
- ln 2 — Natural log of 2
- Digit 21,481 = 4
- γ — Euler-Mascheroni (γ)
- Digit 21,481 = 3
Also seen as
Prime neighborhood
Unicode codepoint
叩
CJK Unified Ideograph-53E9
U+53E9
Other letter (Lo)
UTF-8 encoding: E5 8F A9 (3 bytes).
Hex color
#0053E9
RGB(0, 83, 233)
IPv4 address
As an unsigned 32-bit integer, this is the IPv4 address 0.0.83.233.
- Address
- 0.0.83.233
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.83.233
Unspecified address (0.0.0.0/8) — "this network" placeholder.
Position in π
The digit sequence 21481 first appears in π at position 203,225 of the decimal expansion (the 203,225ordinal-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.