DivisorSigma[k, n] gives the divisor function \[Sigma]_k (n).
GegenbauerC[n, m, x] gives the Gegenbauer polynomial C_n^(m)(x). GegenbauerC[n, x] gives the renormalized form lim_(m->0) C_n^(m)(x)/m.
WeatherData[loc, " property"] gives the most recent measurement for the specified weather property at the location corresponding to loc.WeatherData[loc, " property", date] ...
VectorStyle is an option to VectorPlot, ListVectorPlot, and related functions that determines the style to use for drawing field vectors.
Play
(Built-in Mathematica Symbol) Play[f, {t, t_min, t_max}] creates an object that plays as a sound whose amplitude is given by f as a function of time t in seconds between t_min and t_max.
InverseJacobiDC[v, m] gives the inverse Jacobi elliptic function dc -1 (v \[VerticalSeparator] m).
InverseJacobiNS[v, m] gives the inverse Jacobi elliptic function ns -1 (v \[VerticalSeparator] m).
WeierstrassHalfPeriods[{g_2, g_3}] gives the half-periods {\[Omega], \[Omega]^\[Prime]} for Weierstrass elliptic functions corresponding to the invariants {g_2, g_3}.
SpokenString[expr] gives a string of text corresponding to a spoken representation of the expression expr.
Degree
(Built-in Mathematica Symbol) Degree gives the number of radians in one degree. It has a numerical value of \[Pi]/180.