Most common statistics about variables in a data set can come from Proc freq, and for numeric variables Proc Means, Summary and/or Univariate.
If the data has a complex weighting requirement then perhaps Proc SurveyFreq or SurveyMeans.
Statistics about datasets tend to be things like number of records, number of variables, size of records, total set size. Is that what you want? Some of that comes from Proc Contents.