View source for 219 (number)

{{Infobox number
| number = 219
}}
'''219''' ('''two hundred [and] nineteen''') is the [[Natural number|natural number]] following [[218 (number)|218]] and preceding [[220 (number)|220]].

==In mathematics==
*219 is a [[Happy number|happy number]].<ref>{{Cite OEIS|A007770|name=Happy numbers}}</ref>
*[[Mertens function]](219) = 4, a record high.<ref>{{Cite OEIS|sequencenumber=A051400|name=Smallest value of x such that M(x)=n, where M() is Mertens's function}}</ref>
*There are 219 [[Partially ordered set|partially ordered set]]s on four labeled elements.<ref>{{Cite OEIS|sequencenumber=A001035|name=Number of partially ordered sets ("posets") with n labeled elements (or labeled acyclic transitive digraphs)}}</ref>
*219 is the smallest number that can be represented as a sum of four positive cubes in two different ways.<ref>{{Cite OEIS|sequencenumber=A025420|name=Least sum of 4 positive cubes in exactly n ways}}.</ref>
*There are 219 different [[Space group|space group]]s, discrete and full-dimensional sets of symmetries of three-dimensional space or of crystal structures.

==References==
{{reflist}}

[[Category:Integers]]

{{Sourceattribution|219 (number)}}