It's definitely alphabetical order. This is from Wiki:
When compounds contain more than one functional group, the order of precedence determines which groups are named with prefix or suffix forms. The highest precedence group takes the suffix, with all others taking the prefix form. However, double and triple bonds only take suffix form (-en and -yn) and are used with other suffixes.
Prefixed substituents are ordered alphabetically (excluding any modifiers such as di-, tri-, etc.), e.g. chlorofluoromethane, not fluorochloromethane. If there are multiple functional groups of the same type, either prefixed or suffixed, the position numbers are ordered numerically (thus ethane-1,2-diol, not ethane-2,1-diol.) The N position indicator for amines and amides comes before "1", e.g. CH3CH(CH3)CH2NH(CH3) is N,2-dimethylpropanamine.
Edit: Maybe anna is right. I know the NEAP book puts alkyl groups ahead of alkyl halides.
e.g. it said methylcholoropentane, which is not in alphabetical order. it was something like that. but that is weird, as alkyl halides>alkyl groups.
this stuff is confusing!