Number
21,997
21,997 is a prime, odd.
Properties
- Parity
- Odd
- Digit count
- 5
- Digit sum
- 28
- Digit product
- 1,134
- Digital root
- 1
- Palindrome
- No
- Bit width
- 15 bits
- Reversed
- 79,912
- Recamán's sequence
- a(167,769) = 21,997
- Square (n²)
- 483,868,009
- Cube (n³)
- 10,643,644,593,973
- Divisor count
- 2
- σ(n) — sum of divisors
- 21,998
- φ(n) — Euler's totient
- 21,996
Primality
21,997 is prime. It has exactly two divisors: 1 and itself.
Divisors & multiples
Aliquot sum (sum of proper divisors):
1
First multiples
21,997
·
43,994
(double)
·
65,991
·
87,988
·
109,985
·
131,982
·
153,979
·
175,976
·
197,973
·
219,970
Sums & aliquot sequence
As a sum of two squares:
46² + 141²
As consecutive integers:
10,998 + 10,999
Representations
- In words
- twenty-one thousand nine hundred ninety-seven
- Ordinal
- 21997th
- Binary
- 101010111101101
- Octal
- 52755
- Hexadecimal
- 0x55ED
- Base64
- Ve0=
- One's complement
- 43,538 (16-bit)
In other bases
ternary (3)
1010011201
quaternary (4)
11113231
quinary (5)
1200442
senary (6)
245501
septenary (7)
121063
nonary (9)
33151
undecimal (11)
15588
duodecimal (12)
10891
tridecimal (13)
a021
tetradecimal (14)
8033
pentadecimal (15)
67b7
Historical numeral systems
- Babylonian (base 60)
- 𒁹𒁹𒁹𒁹𒁹𒁹 𒁹𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹𒁹
- Egyptian hieroglyphic
- 𓂍𓂍𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓏺𓏺𓏺𓏺𓏺𓏺𓏺
- Greek (Milesian)
- ͵καϡϟζʹ
- Mayan (base 20)
- 𝋢·𝋮·𝋳·𝋱
- Chinese
- 二萬一千九百九十七
- Chinese (financial)
- 貳萬壹仟玖佰玖拾柒
In other modern scripts
Eastern Arabic
٢١٩٩٧
Devanagari
२१९९७
Bengali
২১৯৯৭
Tamil
௨௧௯௯௭
Thai
๒๑๙๙๗
Tibetan
༢༡༩༩༧
Khmer
២១៩៩៧
Lao
໒໑໙໙໗
Burmese
၂၁၉၉၇
Digit at this position in famous constants
- π — Pi (π)
- Digit 21,997 = 7
- e — Euler's number (e)
- Digit 21,997 = 6
- φ — Golden ratio (φ)
- Digit 21,997 = 7
- √2 — Pythagoras's (√2)
- Digit 21,997 = 4
- ln 2 — Natural log of 2
- Digit 21,997 = 6
- γ — Euler-Mascheroni (γ)
- Digit 21,997 = 9
Also seen as
Prime neighborhood
Unicode codepoint
嗭
CJK Unified Ideograph-55Ed
U+55ED
Other letter (Lo)
UTF-8 encoding: E5 97 AD (3 bytes).
Hex color
#0055ED
RGB(0, 85, 237)
IPv4 address
As an unsigned 32-bit integer, this is the IPv4 address 0.0.85.237.
- Address
- 0.0.85.237
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.85.237
Unspecified address (0.0.0.0/8) — "this network" placeholder.
Position in π
The digit sequence 21997 first appears in π at position 30,170 of the decimal expansion (the 30,170ordinal-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.