Count, tell, enumerate, number are comparable when they mean to ascertain the total of units in a collectionby noting one after another or one group after another.
Count (see also RELY) implies computation of a total by assigning to each unit or each group of units as noted its proper numeral in succession, such as one, two, three . . . or three, six, nine . . .
Tell, which is somewhat old-fashioned in general use, usually stresses a counting one by one or it may suggest a lingering counting interspersed with meditation on each unit counted.
Tell is more common in current use in the collocation tell off which adds to the notion of counting that of setting apart the units counted.
Enumerate implies a listing or mentioning of each one in a series not only that their total may be ascertained, but that they may be individually known or specified.
Number is a somewhat literary equivalent of either count or enumerate; in some uses it carries an additional suggestion of allotment or limit.