128,442
128,442 is a composite number, even.
128,442 (one hundred twenty-eight thousand four hundred forty-two) is an even 6-digit number. It is a composite number with 8 divisors, and factors as 2 × 3 × 21,407. Its proper divisors sum to 128,454, more than the number itself, making it an abundant number. Written other ways, in hexadecimal, 0x1F5BA.
Interestingness
Properties
- Parity
- Even
- Digit count
- 6
- Digit sum
- 21
- Digit product
- 512
- Digital root
- 3
- Palindrome
- No
- Bit width
- 17 bits
- Reversed
- 244,821
- Recamán's sequence
- a(232,756) = 128,442
- Square (n²)
- 16,497,347,364
- Cube (n³)
- 2,118,952,290,126,888
- Divisor count
- 8
- σ(n) — sum of divisors
- 256,896
- φ(n) — Euler's totient
- 42,812
- Sum of prime factors
- 21,412
Primality
Prime factorization: 2 × 3 × 21407
Divisors & multiples
Sums & aliquot sequence
Continued fraction of √n
√128,442 = [358; (2, 1, 1, 2, 1, 2, 1, 118, 1, 2, 1, 2, 1, 1, 2, 716)]
Period length 16 — the block in parentheses repeats forever.
Representations
- In words
- one hundred twenty-eight thousand four hundred forty-two
- Ordinal
- 128442nd
- Binary
- 11111010110111010
- Octal
- 372672
- Hexadecimal
- 0x1F5BA
- Base64
- AfW6
- One's complement
- 4,294,838,853 (32-bit)
- Scientific notation
- 1.28442 × 10⁵
- As a duration
- 128,442 s = 1 day, 11 hours, 40 minutes, 42 seconds
As an angle
Historical numeral systems
- Babylonian (base 60)
- 𒌋𒌋𒌋𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋 𒌋𒌋𒌋𒌋𒁹𒁹
- Egyptian hieroglyphic
- 𓆐𓂍𓂍𓆼𓆼𓆼𓆼𓆼𓆼𓆼𓆼𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓎆𓏺𓏺
- Greek (Milesian)
- ͵ρκηυμβʹ
- Mayan (base 20)
- 𝋰·𝋡·𝋢·𝋢
- Chinese
- 一十二萬八千四百四十二
- Chinese (financial)
- 壹拾貳萬捌仟肆佰肆拾貳
Also seen as
Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 128442, here are decompositions:
- 5 + 128437 = 128442
- 11 + 128431 = 128442
- 29 + 128413 = 128442
- 31 + 128411 = 128442
- 43 + 128399 = 128442
- 53 + 128389 = 128442
- 101 + 128341 = 128442
- 103 + 128339 = 128442
Showing the first eight; more decompositions exist.
UTF-8 encoding: F0 9F 96 BA (4 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.1.245.186.
- Address
- 0.1.245.186
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.1.245.186
Unspecified address (0.0.0.0/8) — "this network" placeholder.
This number falls in the range of US utility patent numbers. If it's a patent, it would be issued as US 128,442 and was likely granted around 1872.
Patent numbers below 100,000 are excluded as too ambiguous; modern numbering currently reaches roughly 12.5 million.
Related reading
- Babylonian numerals — The base-60 cuneiform system that gave us 60 minutes, 60 seconds, and 360°.