Modulo calculation method and device

In a data processing method, a remainder R that is produced during the division of an integer A by a prescribed integer B is calculated recursively. For this purpose, a data symbol word representing the integer A is decomposed into K data symbol part-words W<SUB>0</SUB>, W<SUB>1</SUB>, . . . , W<SUB>K-1 </SUB>of word length L, and in each recursion step a function F determined by the numbers B and L is applied to an argument that depends on the function value F<SUB>i-1 </SUB>obtained in the preceding recursion step, and on a data symbol part-word W<SUB>K-i</SUB>.