991,440
991,440 is a composite number, even.
991,440 (nine hundred ninety-one thousand four hundred forty) is an even 6-digit number. It is a composite number with 140 divisors, and factors as 2⁴ × 3⁶ × 5 × 17. Its proper divisors sum to 2,667,924, more than the number itself, making it an abundant number. Written other ways, in hexadecimal, 0xF20D0.
Interestingness
Properties
Primality
Prime factorization: 2 4 × 3 6 × 5 × 17
Divisors & multiples
Sums & aliquot sequence
Continued fraction of √n
√991,440 = [995; (1, 2, 2, 5, 2, 2, 1, 1990)]
Period length 8 — the block in parentheses repeats forever.
Representations
- In words
- nine hundred ninety-one thousand four hundred forty
- Ordinal
- 991440th
- Binary
- 11110010000011010000
- Octal
- 3620320
- Hexadecimal
- 0xF20D0
- Base64
- DyDQ
- One's complement
- 4,293,975,855 (32-bit)
- Scientific notation
- 9.9144 × 10⁵
- As a duration
- 991,440 s = 11 days, 11 hours, 24 minutes
As an angle
Historical numeral systems
- Babylonian (base 60)
- 𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒁹𒁹𒁹𒁹 ·
- Egyptian hieroglyphic
- 𓆐𓆐𓆐𓆐𓆐𓆐𓆐𓆐𓆐𓂍𓂍𓂍𓂍𓂍𓂍𓂍𓂍𓂍𓆼𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓎆
- Greek (Milesian)
- ͵ϡϟαυμʹ
- Chinese
- 九十九萬一千四百四十
- Chinese (financial)
- 玖拾玖萬壹仟肆佰肆拾
Also seen as
Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 991440, here are decompositions:
- 11 + 991429 = 991440
- 13 + 991427 = 991440
- 31 + 991409 = 991440
- 53 + 991387 = 991440
- 59 + 991381 = 991440
- 83 + 991357 = 991440
- 97 + 991343 = 991440
- 113 + 991327 = 991440
Showing the first eight; more decompositions exist.
As an unsigned 32-bit integer, this is the IPv4 address 0.15.32.208.
- Address
- 0.15.32.208
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.15.32.208
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 991,440 and was likely granted around 1911.
Patent numbers below 100,000 are excluded as too ambiguous; modern numbering currently reaches roughly 12.5 million.
The digit sequence 991440 first appears in π at position 187,804 of the decimal expansion (the 187,804ordinal-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°.