287 (number)
| ||||
|---|---|---|---|---|
| Cardinal | two hundred eighty-seven | |||
| Ordinal | 287th (two hundred eighty-seventh) | |||
| Factorization | 7 × 41 | |||
| Divisors | 1, 7, 41, 287 | |||
| Greek numeral | ΣΠΖ´ | |||
| Roman numeral | CCLXXXVII | |||
| Binary | 1000111112 | |||
| Ternary | 1011223 | |||
| Senary | 11556 | |||
| Octal | 4378 | |||
| Duodecimal | 1BB12 | |||
| Hexadecimal | 11F16 | |||
287 is the natural number following 286 and preceding 288.
In mathematics
[edit]- 287 is an odd composite number with 2 prime factors.[1]
- 287 is the sum of consecutive primes in three different ways, 89+97+101, 43+53+59+61+67, and 17+19+23+29+31+37+41+43+47
- 287 is a pentagonal number which follows the concept of triangular numbers.[2]
- 287 is an odd semiprime number.[3]
- 287 is the sum of exactly 4 nonzero squares.[4]
- 287 is a number where 2(287)-1 and 2(287)+1 are both prime.[5]
World Records
[edit]- On November 15, 2012, in the United Kingdom, the largest toy construction lesson was achieved with 287 participants.[6]
- On August 8, 2018, in Japan, the largest blind soccer (football) lesson was completed with 287 members.[7]
- On February 28, 2020, the largest Welsh folk dance was completed in Swansea in the United Kingdom. There were 287 participants.[8]
- On June 20, 2009, Bora Milutinović completed the Guinness World Record for the greatest number of international soccer matches a coach has been in charge of. He was at 287 games.[9]
- On December 20, 2020, the largest group of people dressed as the sun was completed in Guangzhou, China. There were 287 participants.[10]
Other fields
[edit]- The calendar years 287 AD and 287 BC.
- 287 is the number of several highways in Brazil, Canada, Japan, and the United States.
- 287 Nephthys is an S-type asteroid in the asteroid belt. It was discovered by Christian Heinrich Friedrich Peters in Clinton, Oneida County, New York. It was named after Nephthys in Egyptian mythology.[11]
References
[edit]- ^ "Composite numbers". mathworld.wolfram.com.
- ^ "Pentagonal number". mathworld.wolfram.com.
- ^ Sloane, N. J. A. (ed.). "Sequence A046315 (Odd semiprimes: odd numbers divisible by exactly 2 primes (counted with multiplicity))". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
- ^ Sloane, N. J. A. (ed.). "Sequence A004215 (Numbers that are the sum of 4 but no fewer nonzero squares)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
- ^ Sloane, N. J. A. (ed.). "Sequence A002822 (Numbers m such that 6m-1, 6m+1 are twin primes)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
- ^ "287 people at a toy making lesson". www.guinnessworldrecords.com.
- ^ "287 person blind soccer lesson". www.guinnessworldrecords.com.
- ^ "287 people in a Welsh folk dance". guinnessworldrecords.com.
- ^ "287 international soccer games by a single coach". www.guinnessworldrecords.com.
- ^ "287 people dressed as the sun". www.guinnessworldrecords.com.
- ^ "287 Nephthys information". in-the-sky.org.