Number
21,401
21,401 is a prime, odd.
Properties
- Parity
- Odd
- Digit count
- 5
- Digit sum
- 8
- Digit product
- 0
- Digital root
- 8
- Palindrome
- No
- Bit width
- 15 bits
- Reversed
- 10,412
- Recamán's sequence
- a(41,037) = 21,401
- Square (n²)
- 458,002,801
- Cube (n³)
- 9,801,717,944,201
- Divisor count
- 2
- σ(n) — sum of divisors
- 21,402
- φ(n) — Euler's totient
- 21,400
Primality
21,401 is prime. It has exactly two divisors: 1 and itself.
Divisors & multiples
Aliquot sum (sum of proper divisors):
1
First multiples
21,401
·
42,802
(double)
·
64,203
·
85,604
·
107,005
·
128,406
·
149,807
·
171,208
·
192,609
·
214,010
Sums & aliquot sequence
As a sum of two squares:
76² + 125²
As consecutive integers:
10,700 + 10,701
Representations
- In words
- twenty-one thousand four hundred one
- Ordinal
- 21401st
- Binary
- 101001110011001
- Octal
- 51631
- Hexadecimal
- 0x5399
- Base64
- U5k=
- One's complement
- 44,134 (16-bit)
In other bases
ternary (3)
1002100122
quaternary (4)
11032121
quinary (5)
1141101
senary (6)
243025
septenary (7)
116252
nonary (9)
32318
undecimal (11)
15096
duodecimal (12)
10475
tridecimal (13)
9983
tetradecimal (14)
7b29
pentadecimal (15)
651b
Historical numeral systems
- Babylonian (base 60)
- 𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒁹
- Egyptian hieroglyphic
- 𓂍𓂍𓆼𓍢𓍢𓍢𓍢𓏺
- Greek (Milesian)
- ͵καυαʹ
- Mayan (base 20)
- 𝋢·𝋭·𝋪·𝋡
- Chinese
- 二萬一千四百零一
- Chinese (financial)
- 貳萬壹仟肆佰零壹
In other modern scripts
Eastern Arabic
٢١٤٠١
Devanagari
२१४०१
Bengali
২১৪০১
Tamil
௨௧௪௦௧
Thai
๒๑๔๐๑
Tibetan
༢༡༤༠༡
Khmer
២១៤០១
Lao
໒໑໔໐໑
Burmese
၂၁၄၀၁
Digit at this position in famous constants
- π — Pi (π)
- Digit 21,401 = 3
- e — Euler's number (e)
- Digit 21,401 = 8
- φ — Golden ratio (φ)
- Digit 21,401 = 9
- √2 — Pythagoras's (√2)
- Digit 21,401 = 0
- ln 2 — Natural log of 2
- Digit 21,401 = 1
- γ — Euler-Mascheroni (γ)
- Digit 21,401 = 2
Also seen as
Prime neighborhood
Unicode codepoint
厙
CJK Unified Ideograph-5399
U+5399
Other letter (Lo)
UTF-8 encoding: E5 8E 99 (3 bytes).
Hex color
#005399
RGB(0, 83, 153)
IPv4 address
As an unsigned 32-bit integer, this is the IPv4 address 0.0.83.153.
- Address
- 0.0.83.153
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.83.153
Unspecified address (0.0.0.0/8) — "this network" placeholder.
Position in π
The digit sequence 21401 first appears in π at position 160,003 of the decimal expansion (the 160,003ordinal-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.