To install click the Add extension button. That's it.

The source code for the WIKI 2 extension is being checked by specialists of the Mozilla Foundation, Google, and Apple. You could also do it yourself at any point in time.

4,5
Kelly Slayton
Congratulations on this excellent venture… what a great idea!
Alexander Grigorievskiy
I use WIKI 2 every day and almost forgot how the original Wikipedia looks like.
Live Statistics
English Articles
Improved in 24 Hours
What we do. Every page goes through several hundred of perfecting techniques; in live mode. Quite the same Wikipedia. Just better.
.
Leo
Newton
Brights
Milds

# 215 (number)

 ← 214 215 216 →
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
Quaternary 31134
Quinary 13305
Senary 5556
Octal 3278
Duodecimal 15B12
Vigesimal AF20
Base 36 5Z36

215 (two hundred [and] fifteen) is the natural number following 214 and preceding 216.

• 1/1
Views:
2 473
• Lou Fant-Kids Do The Strangest Things (ASL)

## In mathematics

• 215 is a composite number and a semiprime.
• ${\displaystyle 215=(3!)^{3}-1}$
• 215 is the second smallest integer (after 5) such that ${\displaystyle n^{2}-17}$ is twice a square: ${\displaystyle 215^{2}-17=2\times 152^{2}}$.[1]
• 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).

215 is also:

## References

1. ^ (sequence A144796 in the OEIS)
2. ^ (sequence A002967 in the OEIS)