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Number

21,493

21,493 is a prime, odd.

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

Properties

Parity
Odd
Digit count
5
Digit sum
19
Digit product
216
Digital root
1
Palindrome
No
Bit width
15 bits
Reversed
39,412
Recamán's sequence
a(40,853) = 21,493
Square (n²)
461,949,049
Cube (n³)
9,928,670,910,157
Divisor count
2
σ(n) — sum of divisors
21,494
φ(n) — Euler's totient
21,492

Primality

21,493 is prime. It has exactly two divisors: 1 and itself.

Divisors & multiples

All divisors (2)
1 · 21493
Aliquot sum (sum of proper divisors): 1
Factor pairs (a × b = 21,493)
1 × 21493
First multiples
21,493 · 42,986 (double) · 64,479 · 85,972 · 107,465 · 128,958 · 150,451 · 171,944 · 193,437 · 214,930

Sums & aliquot sequence

As a sum of two squares: 87² + 118²
As consecutive integers: 10,746 + 10,747

Representations

In words
twenty-one thousand four hundred ninety-three
Ordinal
21493rd
Binary
101001111110101
Octal
51765
Hexadecimal
0x53F5
Base64
U/U=
One's complement
44,042 (16-bit)
In other bases
ternary (3) 1002111001
quaternary (4) 11033311
quinary (5) 1141433
senary (6) 243301
septenary (7) 116443
nonary (9) 32431
undecimal (11) 1516a
duodecimal (12) 10531
tridecimal (13) 9a24
tetradecimal (14) 7b93
pentadecimal (15) 657d

Historical numeral systems

Babylonian (base 60)
𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹 𒌋𒁹𒁹𒁹
Egyptian hieroglyphic
𓂍𓂍𓆼𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓏺𓏺𓏺
Greek (Milesian)
͵καυϟγʹ
Mayan (base 20)
𝋢·𝋭·𝋮·𝋭
Chinese
二萬一千四百九十三
Chinese (financial)
貳萬壹仟肆佰玖拾參
In other modern scripts
Eastern Arabic ٢١٤٩٣ Devanagari २१४९३ Bengali ২১৪৯৩ Tamil ௨௧௪௯௩ Thai ๒๑๔๙๓ Tibetan ༢༡༤༩༣ Khmer ២១៤៩៣ Lao ໒໑໔໙໓ Burmese ၂၁၄၉၃

Digit at this position in famous constants

π — Pi (π)
Digit 21,493 = 9
e — Euler's number (e)
Digit 21,493 = 5
φ — Golden ratio (φ)
Digit 21,493 = 5
√2 — Pythagoras's (√2)
Digit 21,493 = 6
ln 2 — Natural log of 2
Digit 21,493 = 4
γ — Euler-Mascheroni (γ)
Digit 21,493 = 6

Also seen as

Prime neighborhood

Adjacent primes:

  • Previous prime: 21,491 (gap of 2)
  • Next prime: 21,499 (gap of 6)

Pair status: twin with 21491, sexy with 21499.

Unicode codepoint
CJK Unified Ideograph-53F5
U+53F5
Other letter (Lo)

UTF-8 encoding: E5 8F B5 (3 bytes).

Hex color
#0053F5
RGB(0, 83, 245)
IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.83.245.

Address
0.0.83.245
Class
reserved
IPv4-mapped IPv6
::ffff:0.0.83.245

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

Position in π

The digit sequence 21493 first appears in π at position 101,749 of the decimal expansion (the 101,749ordinal-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.