13,921
13,921 is a prime, odd.
13,921 (thirteen thousand nine hundred twenty-one) is an odd 5-digit number. It is a prime number — divisible only by 1 and itself. Written other ways, in hexadecimal, 0x3661.
Interestingness
Properties
- Parity
- Odd
- Digit count
- 5
- Digit sum
- 16
- Digit product
- 54
- Digital root
- 7
- Palindrome
- No
- Bit width
- 14 bits
- Reversed
- 12,931
- Recamán's sequence
- a(20,874) = 13,921
- Square (n²)
- 193,794,241
- Cube (n³)
- 2,697,809,628,961
- Divisor count
- 2
- σ(n) — sum of divisors
- 13,922
- φ(n) — Euler's totient
- 13,920
Primality
13,921 is prime. It has exactly two divisors: 1 and itself.
Divisors & multiples
Sums & aliquot sequence
Continued fraction of √n
√13,921 = [117; (1, 77, 1, 1, 1, 25, 1, 1, 4, 8, 1, 1, 13, 2, 1, 5, 4, 2, 4, 1, 1, 2, 1, 6, …)]
Representations
- In words
- thirteen thousand nine hundred twenty-one
- Ordinal
- 13921st
- Binary
- 11011001100001
- Octal
- 33141
- Hexadecimal
- 0x3661
- Base64
- NmE=
- One's complement
- 51,614 (16-bit)
- Scientific notation
- 1.3921 × 10⁴
- As a duration
- 13,921 s = 3 hours, 52 minutes, 1 second
As an angle
Historical numeral systems
- Babylonian (base 60)
- 𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒌋𒁹𒁹 𒁹
- Egyptian hieroglyphic
- 𓂍𓆼𓆼𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓎆𓏺
- Greek (Milesian)
- ͵ιγϡκαʹ
- Mayan (base 20)
- 𝋡·𝋮·𝋰·𝋡
- Chinese
- 一萬三千九百二十一
- Chinese (financial)
- 壹萬參仟玖佰貳拾壹
Digit at this position in famous constants
- π — Pi (π)
- Digit 13,921 = 6
- e — Euler's number (e)
- Digit 13,921 = 5
- φ — Golden ratio (φ)
- Digit 13,921 = 4
- √2 — Pythagoras's (√2)
- Digit 13,921 = 7
- ln 2 — Natural log of 2
- Digit 13,921 = 6
- γ — Euler-Mascheroni (γ)
- Digit 13,921 = 4
Also seen as
UTF-8 encoding: E3 99 A1 (3 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.0.54.97.
- Address
- 0.0.54.97
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.54.97
Unspecified address (0.0.0.0/8) — "this network" placeholder.
Heard as a frequency, 13,921 Hz is closest to:
- Concert pitch (A4 = 440 Hz): A9 (14080 Hz, -20¢)
- Scientific pitch (C4 = 256 Hz): A9 (13777.2 Hz, +18¢)
- Baroque pitch (A4 = 415 Hz): A♯9 (14069.7 Hz, -18¢)
The digit sequence 13921 first appears in π at position 12,194 of the decimal expansion (the 12,194ordinal-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.
- Egyptian hieroglyphic numerals — Seven hieroglyphs for every power of ten, from a single stroke to a million.