number.wiki
Number

20,521

20,521 is a prime, odd.

Arithmetic Number Balanced Prime Chen Prime Deficient Number Odious Number Pernicious Number Prime Pythagorean Prime Recamán's Sequence Squarefree

Properties

Parity
Odd
Digit count
5
Digit sum
10
Digit product
0
Digital root
1
Palindrome
No
Bit width
15 bits
Reversed
12,502
Recamán's sequence
a(86,174) = 20,521
Square (n²)
421,111,441
Cube (n³)
8,641,627,880,761
Divisor count
2
σ(n) — sum of divisors
20,522
φ(n) — Euler's totient
20,520

Primality

20,521 is prime. It has exactly two divisors: 1 and itself.

Divisors & multiples

All divisors (2)
1 · 20521
Aliquot sum (sum of proper divisors): 1
Factor pairs (a × b = 20,521)
1 × 20521
First multiples
20,521 · 41,042 (double) · 61,563 · 82,084 · 102,605 · 123,126 · 143,647 · 164,168 · 184,689 · 205,210

Sums & aliquot sequence

As a sum of two squares: 45² + 136²
As consecutive integers: 10,260 + 10,261

Representations

In words
twenty thousand five hundred twenty-one
Ordinal
20521st
Binary
101000000101001
Octal
50051
Hexadecimal
0x5029
Base64
UCk=
One's complement
45,014 (16-bit)
In other bases
ternary (3) 1001011001
quaternary (4) 11000221
quinary (5) 1124041
senary (6) 235001
septenary (7) 113554
nonary (9) 31131
undecimal (11) 14466
duodecimal (12) ba61
tridecimal (13) 9457
tetradecimal (14) 769b
pentadecimal (15) 6131

Historical numeral systems

Babylonian (base 60)
𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒁹𒁹 𒁹
Egyptian hieroglyphic
𓂍𓂍𓍢𓍢𓍢𓍢𓍢𓎆𓎆𓏺
Greek (Milesian)
͵κφκαʹ
Mayan (base 20)
𝋢·𝋫·𝋦·𝋡
Chinese
二萬零五百二十一
Chinese (financial)
貳萬零伍佰貳拾壹
In other modern scripts
Eastern Arabic ٢٠٥٢١ Devanagari २०५२१ Bengali ২০৫২১ Tamil ௨௦௫௨௧ Thai ๒๐๕๒๑ Tibetan ༢༠༥༢༡ Khmer ២០៥២១ Lao ໒໐໕໒໑ Burmese ၂၀၅၂၁

Digit at this position in famous constants

π — Pi (π)
Digit 20,521 = 0
e — Euler's number (e)
Digit 20,521 = 1
φ — Golden ratio (φ)
Digit 20,521 = 1
√2 — Pythagoras's (√2)
Digit 20,521 = 2
ln 2 — Natural log of 2
Digit 20,521 = 6
γ — Euler-Mascheroni (γ)
Digit 20,521 = 1

Also seen as

Prime neighborhood

Adjacent primes:

  • Previous prime: 20,509 (gap of 12)
  • Next prime: 20,533 (gap of 12)
Unicode codepoint
CJK Unified Ideograph-5029
U+5029
Other letter (Lo)

UTF-8 encoding: E5 80 A9 (3 bytes).

Hex color
#005029
RGB(0, 80, 41)
IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.80.41.

Address
0.0.80.41
Class
reserved
IPv4-mapped IPv6
::ffff:0.0.80.41

Unspecified address (0.0.0.0/8) — "this network" placeholder.

Position in π

The digit sequence 20521 first appears in π at position 142,428 of the decimal expansion (the 142,428ordinal-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.