number.wiki
Number

20,509

20,509 is a prime, odd.

Arithmetic Number Deficient Number Evil Number Prime Pythagorean Prime Recamán's Sequence Squarefree Twin Prime

Properties

Parity
Odd
Digit count
5
Digit sum
16
Digit product
0
Digital root
7
Palindrome
No
Bit width
15 bits
Reversed
90,502
Recamán's sequence
a(86,198) = 20,509
Square (n²)
420,619,081
Cube (n³)
8,626,476,732,229
Divisor count
2
σ(n) — sum of divisors
20,510
φ(n) — Euler's totient
20,508

Primality

20,509 is prime. It has exactly two divisors: 1 and itself.

Divisors & multiples

All divisors (2)
1 · 20509
Aliquot sum (sum of proper divisors): 1
Factor pairs (a × b = 20,509)
1 × 20509
First multiples
20,509 · 41,018 (double) · 61,527 · 82,036 · 102,545 · 123,054 · 143,563 · 164,072 · 184,581 · 205,090

Sums & aliquot sequence

As a sum of two squares: 75² + 122²
As consecutive integers: 10,254 + 10,255

Representations

In words
twenty thousand five hundred nine
Ordinal
20509th
Binary
101000000011101
Octal
50035
Hexadecimal
0x501D
Base64
UB0=
One's complement
45,026 (16-bit)
In other bases
ternary (3) 1001010121
quaternary (4) 11000131
quinary (5) 1124014
senary (6) 234541
septenary (7) 113536
nonary (9) 31117
undecimal (11) 14455
duodecimal (12) ba51
tridecimal (13) 9448
tetradecimal (14) 768d
pentadecimal (15) 6124

Historical numeral systems

Babylonian (base 60)
𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒁹 𒌋𒌋𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹
Egyptian hieroglyphic
𓂍𓂍𓍢𓍢𓍢𓍢𓍢𓏺𓏺𓏺𓏺𓏺𓏺𓏺𓏺𓏺
Greek (Milesian)
͵κφθʹ
Mayan (base 20)
𝋢·𝋫·𝋥·𝋩
Chinese
二萬零五百零九
Chinese (financial)
貳萬零伍佰零玖
In other modern scripts
Eastern Arabic ٢٠٥٠٩ Devanagari २०५०९ Bengali ২০৫০৯ Tamil ௨௦௫௦௯ Thai ๒๐๕๐๙ Tibetan ༢༠༥༠༩ Khmer ២០៥០៩ Lao ໒໐໕໐໙ Burmese ၂၀၅၀၉

Digit at this position in famous constants

π — Pi (π)
Digit 20,509 = 6
e — Euler's number (e)
Digit 20,509 = 6
φ — Golden ratio (φ)
Digit 20,509 = 6
√2 — Pythagoras's (√2)
Digit 20,509 = 6
ln 2 — Natural log of 2
Digit 20,509 = 6
γ — Euler-Mascheroni (γ)
Digit 20,509 = 6

Also seen as

Prime neighborhood

Adjacent primes:

  • Previous prime: 20,507 (gap of 2)
  • Next prime: 20,521 (gap of 12)

Pair status: twin with 20507.

Unicode codepoint
CJK Unified Ideograph-501D
U+501D
Other letter (Lo)

UTF-8 encoding: E5 80 9D (3 bytes).

Hex color
#00501D
RGB(0, 80, 29)
IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.80.29.

Address
0.0.80.29
Class
reserved
IPv4-mapped IPv6
::ffff:0.0.80.29

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

Position in π

The digit sequence 20509 first appears in π at position 45,908 of the decimal expansion (the 45,908ordinal-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.