128,400
128,400 is a composite number, even.
128,400 (one hundred twenty-eight thousand four hundred) is an even 6-digit number. It is a composite number with 60 divisors, and factors as 2⁴ × 3 × 5² × 107. Its proper divisors sum to 286,752, more than the number itself, making it an abundant number. Written other ways, in hexadecimal, 0x1F590.
Interestingness
Properties
- Parity
- Even
- Digit count
- 6
- Digit sum
- 15
- Digit product
- 0
- Digital root
- 6
- Palindrome
- No
- Bit width
- 17 bits
- Reversed
- 4,821
- Recamán's sequence
- a(232,840) = 128,400
- Square (n²)
- 16,486,560,000
- Cube (n³)
- 2,116,874,304,000,000
- Divisor count
- 60
- σ(n) — sum of divisors
- 415,152
- φ(n) — Euler's totient
- 33,920
- Sum of prime factors
- 128
Primality
Prime factorization: 2 4 × 3 × 5 2 × 107
Divisors & multiples
Sums & aliquot sequence
Continued fraction of √n
√128,400 = [358; (3, 28, 3, 716)]
Period length 4 — the block in parentheses repeats forever.
Representations
- In words
- one hundred twenty-eight thousand four hundred
- Ordinal
- 128400th
- Binary
- 11111010110010000
- Octal
- 372620
- Hexadecimal
- 0x1F590
- Base64
- AfWQ
- One's complement
- 4,294,838,895 (32-bit)
- Scientific notation
- 1.284 × 10⁵
- As a duration
- 128,400 s = 1 day, 11 hours, 40 minutes
As an angle
Historical numeral systems
- Babylonian (base 60)
- 𒌋𒌋𒌋𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋 ·
- Egyptian hieroglyphic
- 𓆐𓂍𓂍𓆼𓆼𓆼𓆼𓆼𓆼𓆼𓆼𓍢𓍢𓍢𓍢
- Greek (Milesian)
- ͵ρκηυʹ
- Mayan (base 20)
- 𝋰·𝋡·𝋠·𝋠
- Chinese
- 一十二萬八千四百
- Chinese (financial)
- 壹拾貳萬捌仟肆佰
Also seen as
Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 128400, here are decompositions:
- 7 + 128393 = 128400
- 11 + 128389 = 128400
- 23 + 128377 = 128400
- 53 + 128347 = 128400
- 59 + 128341 = 128400
- 61 + 128339 = 128400
- 73 + 128327 = 128400
- 79 + 128321 = 128400
Showing the first eight; more decompositions exist.
UTF-8 encoding: F0 9F 96 90 (4 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.1.245.144.
- Address
- 0.1.245.144
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.1.245.144
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 128,400 and was likely granted around 1872.
Patent numbers below 100,000 are excluded as too ambiguous; modern numbering currently reaches roughly 12.5 million.
The digit sequence 128400 first appears in π at position 467,296 of the decimal expansion (the 467,296ordinal-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
- Babylonian numerals — The base-60 cuneiform system that gave us 60 minutes, 60 seconds, and 360°.