13,991
13,991 is a composite number, odd.
13,991 (thirteen thousand nine hundred ninety-one) is an odd 5-digit number. It is a composite number with 4 divisors, and factors as 17 × 823. Written other ways, in hexadecimal, 0x36A7.
Interestingness
Properties
- Parity
- Odd
- Digit count
- 5
- Digit sum
- 23
- Digit product
- 243
- Digital root
- 5
- Palindrome
- No
- Bit width
- 14 bits
- Reversed
- 19,931
- Recamán's sequence
- a(20,734) = 13,991
- Square (n²)
- 195,748,081
- Cube (n³)
- 2,738,711,401,271
- Divisor count
- 4
- σ(n) — sum of divisors
- 14,832
- φ(n) — Euler's totient
- 13,152
- Sum of prime factors
- 840
Primality
Prime factorization: 17 × 823
Divisors & multiples
Sums & aliquot sequence
Continued fraction of √n
√13,991 = [118; (3, 1, 1, 8, 1, 8, 4, 1, 11, 1, 1, 1, 4, 1, 5, 2, 2, 17, 1, 3, 1, 3, 1, 1, …)]
Period length 52 — the block in parentheses repeats forever.
Representations
- In words
- thirteen thousand nine hundred ninety-one
- Ordinal
- 13991st
- Binary
- 11011010100111
- Octal
- 33247
- Hexadecimal
- 0x36A7
- Base64
- Nqc=
- One's complement
- 51,544 (16-bit)
- Scientific notation
- 1.3991 × 10⁴
- As a duration
- 13,991 s = 3 hours, 53 minutes, 11 seconds
As an angle
Historical numeral systems
- Babylonian (base 60)
- 𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒌋𒁹𒁹𒁹 𒌋𒁹
- Egyptian hieroglyphic
- 𓂍𓆼𓆼𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓏺
- Greek (Milesian)
- ͵ιγϡϟαʹ
- Mayan (base 20)
- 𝋡·𝋮·𝋳·𝋫
- Chinese
- 一萬三千九百九十一
- Chinese (financial)
- 壹萬參仟玖佰玖拾壹
Digit at this position in famous constants
- π — Pi (π)
- Digit 13,991 = 0
- e — Euler's number (e)
- Digit 13,991 = 9
- φ — Golden ratio (φ)
- Digit 13,991 = 1
- √2 — Pythagoras's (√2)
- Digit 13,991 = 8
- ln 2 — Natural log of 2
- Digit 13,991 = 6
- γ — Euler-Mascheroni (γ)
- Digit 13,991 = 0
Also seen as
UTF-8 encoding: E3 9A A7 (3 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.0.54.167.
- Address
- 0.0.54.167
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.54.167
Unspecified address (0.0.0.0/8) — "this network" placeholder.
Heard as a frequency, 13,991 Hz is closest to:
- Concert pitch (A4 = 440 Hz): A9 (14080 Hz, -11¢)
- Scientific pitch (C4 = 256 Hz): A9 (13777.2 Hz, +27¢)
- Baroque pitch (A4 = 415 Hz): A♯9 (14069.7 Hz, -10¢)
The digit sequence 13991 first appears in π at position 13,014 of the decimal expansion (the 13,014ordinal-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
- Mayan numerals — Vigesimal dots-and-bars with a shell zero — one of the earliest true zeros.