| ||||
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Cardinal | two hundred fifteen | |||
Ordinal | 215th (two hundred fifteenth) | |||
Factorization | 5 × 43 | |||
Divisors | 5, 43 | |||
Greek numeral | ΣΙΕ´ | |||
Roman numeral | CCXV | |||
Binary | 110101112 | |||
Ternary | 212223 | |||
Senary | 5556 | |||
Octal | 3278 | |||
Duodecimal | 15B12 | |||
Hexadecimal | D716 |
215 (two hundred [and] fifteen) is the natural number following 214 and preceding 216.
In mathematics
[edit]- 215 is a composite number and a semiprime ().
- .
- 215 is the second smallest integer (after 5) such that is twice a square: .[1]
- 215 is a vertically symmetric number on a calculator display (sequence A053701 in the OEIS).
- There are 215 sequences of four integers, counting re-arrangements as distinct, such that the sum of their reciprocals is 1.[2] These are:
- 24 arrangements of (2,3,7,42), (2,3,8,24), (2,3,9,18), (2,3,10,15), (2,4,5,20) and (2,4,6,12).
- 12 arrangements of (3,3,4,12), (3,4,4,6), (2,3,12,12), (2,4,8,8) and (2,5,5,10).
- 6 arrangements of (3,3,6,6).
- 4 arrangements of (2,6,6,6).
- 1 arrangement of (4,4,4,4).
In other fields
[edit]- 215 Oenone is a main belt asteroid.
- E215 is the E number of Sodium ethyl para-hydroxybenzoate.
- There are several highways numbered 215.
215 is also:
- The Dewey Decimal Classification for Science and religion.
- The year AD 215 or 215 BC
- 215 is often used as slang for marijuana, from California Proposition 215, legalizing it for medical use.
- The first area code of metropolitan Philadelphia, Pennsylvania
Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction