189 (number)
From HandWiki
Short description: Natural number
| ||||
|---|---|---|---|---|
| Cardinal | one hundred eighty-nine | |||
| Ordinal | 189th (one hundred eighty-ninth) | |||
| Factorization | 33 × 7 | |||
| Greek numeral | ΡΠΘ´ | |||
| Roman numeral | CLXXXIX | |||
| Binary | 101111012 | |||
| Ternary | 210003 | |||
| Quaternary | 23314 | |||
| Quinary | 12245 | |||
| Senary | 5136 | |||
| Octal | 2758 | |||
| Duodecimal | 13912 | |||
| Hexadecimal | BD16 | |||
| Vigesimal | 9920 | |||
| Base 36 | 5936 | |||
189 (one hundred [and] eighty-nine) is the natural number following 188 and preceding 190.
In mathematics
189 is a centered cube number[1] and a heptagonal number.[2] The centered cube numbers are the sums of two consecutive cubes, and 189 can be written as sum of two cubes in two ways: 43 + 53 and 63 + (−3)3.[3] The smallest number that can be written as the sum of two positive cubes in two ways is 1729.[4]
There are 189 zeros among the decimal digits of the positive integers with at most three digits.[5]
The largest prime number that can be represented in 256-bit arithmetic is the "ultra-useful prime" 2256 − 189,[6] used in quasi-Monte Carlo methods[7] and in some cryptographic systems.[8]
See also
- The year AD 189 or 189 BC
- List of highways numbered 189
- All pages with titles containing 189
References
- ↑ Sloane, N. J. A., ed. "Sequence A005898 (Centered cube numbers)". OEIS Foundation. https://oeis.org/A005898.
- ↑ Sloane, N. J. A., ed. "Sequence A000566 (Heptagonal numbers)". OEIS Foundation. https://oeis.org/A000566.
- ↑ Sloane, N. J. A., ed. "Sequence A051347 (Numbers that are the sum of two (possibly negative) cubes in at least 2 ways)". OEIS Foundation. https://oeis.org/A051347.
- ↑ Sloane, N. J. A., ed. "Sequence A001235 (Taxi-cab numbers: sums of 2 cubes in more than 1 way)". OEIS Foundation. https://oeis.org/A001235.
- ↑ Sloane, N. J. A., ed. "Sequence A033713 (Number of zeros in numbers 1 to 999..9 (n digits))". OEIS Foundation. https://oeis.org/A033713.
- ↑ Sloane, N. J. A., ed. "Sequence A058220 (Ultra-useful primes: smallest k such that 2^(2^n) - k is prime)". OEIS Foundation. https://oeis.org/A058220.
- ↑ Hechenleitner, Bernhard; Entacher, Karl (2006). "A parallel search for good lattice points using LLL-spectral tests". Journal of Computational and Applied Mathematics 189 (1–2): 424–441. doi:10.1016/j.cam.2005.03.058. See Table 5.
- ↑ Longa, Patrick (2010). "Cryptographic Hardware and Embedded Systems, CHES 2010, 12th International Workshop, Santa Barbara, CA, USA, August 17-20, 2010. Proceedings". in Mangard, Stefan; Standaert, François-Xavier. 6225. Springer. pp. 80–94. doi:10.1007/978-3-642-15031-9_6. See Appendix B.
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