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Number

26,561

26,561 is a prime, odd.

26,561 (twenty-six thousand five hundred sixty-one) is an odd 5-digit number. It is a prime number — divisible only by 1 and itself. Written other ways, in hexadecimal, 0x67C1.

Arithmetic Number Chen Prime Cousin Prime Cube-Free Deficient Number Evil Number Prime Pythagorean Prime Recamán's Sequence Squarefree

Interestingness

Properties

Parity
Odd
Digit count
5
Digit sum
20
Digit product
360
Digital root
2
Palindrome
No
Bit width
15 bits
Reversed
16,562
Recamán's sequence
a(315,218) = 26,561
Square (n²)
705,486,721
Cube (n³)
18,738,432,796,481
Divisor count
2
σ(n) — sum of divisors
26,562
φ(n) — Euler's totient
26,560

Primality

26,561 is prime. It has exactly two divisors: 1 and itself.

Divisors & multiples

All divisors (2)
1 · 26561
Aliquot sum (sum of proper divisors): 1
Factor pairs (a × b = 26,561)
1 × 26561
First multiples
26,561 · 53,122 (double) · 79,683 · 106,244 · 132,805 · 159,366 · 185,927 · 212,488 · 239,049 · 265,610

Sums & aliquot sequence

As a sum of two squares: 31² + 160²
As consecutive integers: 13,280 + 13,281

Continued fraction of √n

√26,561 = [162; (1, 39, 1, 2, 1, 19, 1, 1, 1, 1, 1, 9, 1, 1, 3, 1, 1, 4, 1, 1, 7, 1, 1, 2, …)]

Representations

In words
twenty-six thousand five hundred sixty-one
Ordinal
26561st
Binary
110011111000001
Octal
63701
Hexadecimal
0x67C1
Base64
Z8E=
One's complement
38,974 (16-bit)
Scientific notation
2.6561 × 10⁴
As a duration
26,561 s = 7 hours, 22 minutes, 41 seconds
In other bases
ternary (3) 1100102202
quaternary (4) 12133001
quinary (5) 1322221
senary (6) 322545
septenary (7) 140303
nonary (9) 40382
undecimal (11) 18a57
duodecimal (12) 13455
tridecimal (13) c122
tetradecimal (14) 9973
pentadecimal (15) 7d0b

As an angle

26,561° = 73 × 360° + 281°
281° ≈ 4.904 rad
Compass bearing: W (west)

Historical numeral systems

Babylonian (base 60)
𒁹𒁹𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒁹𒁹 𒌋𒌋𒌋𒌋𒁹
Egyptian hieroglyphic
𓂍𓂍𓆼𓆼𓆼𓆼𓆼𓆼𓍢𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓏺
Greek (Milesian)
͵κϛφξαʹ
Mayan (base 20)
𝋣·𝋦·𝋨·𝋡
Chinese
二萬六千五百六十一
Chinese (financial)
貳萬陸仟伍佰陸拾壹
In other modern scripts
Eastern Arabic ٢٦٥٦١ Devanagari २६५६१ Bengali ২৬৫৬১ Tamil ௨௬௫௬௧ Thai ๒๖๕๖๑ Tibetan ༢༦༥༦༡ Khmer ២៦៥៦១ Lao ໒໖໕໖໑ Burmese ၂၆၅၆၁

Digit at this position in famous constants

π — Pi (π)
Digit 26,561 = 5
e — Euler's number (e)
Digit 26,561 = 9
φ — Golden ratio (φ)
Digit 26,561 = 9
√2 — Pythagoras's (√2)
Digit 26,561 = 4
ln 2 — Natural log of 2
Digit 26,561 = 9
γ — Euler-Mascheroni (γ)
Digit 26,561 = 6

Also seen as

Prime neighborhood

Adjacent primes:

  • Previous prime: 26,557 (gap of 4)
  • Next prime: 26,573 (gap of 12)

Pair status: cousin with 26557.

Unicode codepoint
CJK Unified Ideograph-67C1
U+67C1
Other letter (Lo)

UTF-8 encoding: E6 9F 81 (3 bytes).

Hex color
#0067C1
RGB(0, 103, 193)
IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.103.193.

Address
0.0.103.193
Class
reserved
IPv4-mapped IPv6
::ffff:0.0.103.193

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

Position in π

The digit sequence 26561 first appears in π at position 14,897 of the decimal expansion (the 14,897ordinal-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.

Related reading

  • Prime numbers — The building blocks of arithmetic: what primes are, why they matter, and how we find them.
  • Mayan numerals — Vigesimal dots-and-bars with a shell zero — one of the earliest true zeros.