13,381
13,381 is a prime, odd.
13,381 (thirteen thousand three hundred eighty-one) is an odd 5-digit number. It is a prime number — divisible only by 1 and itself. Written other ways, in hexadecimal, 0x3445.
Interestingness
Properties
- Parity
- Odd
- Digit count
- 5
- Digit sum
- 16
- Digit product
- 72
- Digital root
- 7
- Palindrome
- No
- Bit width
- 14 bits
- Reversed
- 18,331
- Recamán's sequence
- a(47,513) = 13,381
- Square (n²)
- 179,051,161
- Cube (n³)
- 2,395,883,585,341
- Divisor count
- 2
- σ(n) — sum of divisors
- 13,382
- φ(n) — Euler's totient
- 13,380
Primality
13,381 is prime. It has exactly two divisors: 1 and itself.
Divisors & multiples
Sums & aliquot sequence
Continued fraction of √n
√13,381 = [115; (1, 2, 11, 4, 3, 1, 1, 1, 1, 2, 1, 18, 1, 1, 3, 1, 14, 1, 1, 1, 4, 2, 13, 6, …)]
Representations
- In words
- thirteen thousand three hundred eighty-one
- Ordinal
- 13381st
- Binary
- 11010001000101
- Octal
- 32105
- Hexadecimal
- 0x3445
- Base64
- NEU=
- One's complement
- 52,154 (16-bit)
- Scientific notation
- 1.3381 × 10⁴
- As a duration
- 13,381 s = 3 hours, 43 minutes, 1 second
As an angle
Historical numeral systems
- Babylonian (base 60)
- 𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒁹𒁹𒁹 𒁹
- Egyptian hieroglyphic
- 𓂍𓆼𓆼𓆼𓍢𓍢𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓏺
- Greek (Milesian)
- ͵ιγτπαʹ
- Mayan (base 20)
- 𝋡·𝋭·𝋩·𝋡
- Chinese
- 一萬三千三百八十一
- Chinese (financial)
- 壹萬參仟參佰捌拾壹
Digit at this position in famous constants
- π — Pi (π)
- Digit 13,381 = 4
- e — Euler's number (e)
- Digit 13,381 = 6
- φ — Golden ratio (φ)
- Digit 13,381 = 4
- √2 — Pythagoras's (√2)
- Digit 13,381 = 9
- ln 2 — Natural log of 2
- Digit 13,381 = 6
- γ — Euler-Mascheroni (γ)
- Digit 13,381 = 5
Also seen as
UTF-8 encoding: E3 91 85 (3 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.0.52.69.
- Address
- 0.0.52.69
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.52.69
Unspecified address (0.0.0.0/8) — "this network" placeholder.
Heard as a frequency, 13,381 Hz is closest to:
- Concert pitch (A4 = 440 Hz): G♯9 (13289.8 Hz, +12¢)
- Scientific pitch (C4 = 256 Hz): G♯9 (13004 Hz, +49¢ — about midway to A9)
- Baroque pitch (A4 = 415 Hz): A9 (13280 Hz, +13¢)
The digit sequence 13381 first appears in π at position 146,642 of the decimal expansion (the 146,642ordinal-suffix:nd 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.
- Egyptian hieroglyphic numerals — Seven hieroglyphs for every power of ten, from a single stroke to a million.