This is documentation for Mathematica 6, which was
based on an earlier version of the Wolfram Language.
View current documentation (Version 11.1)

FactorTermsList

FactorTermsList[poly]
gives a list in which the first element is the overall numerical factor in poly, and the second element is the polynomial with the overall factor removed.
FactorTermsList[poly, {x1, x2, ...}]
gives a list of factors of poly. The first element in the list is the overall numerical factor. The second element is a factor that does not depend on any of the xi. Subsequent elements are factors which depend on progressively more of the xi.
Pull out an overall numerical factor, but do no further factoring:
In[1]:=
Click for copyable input
Out[1]=
New in 1