Abstract: A predictor configured to predict a parity value of a Carry-Less multiplication result of a multiplicand data string and a multiplier data string being two data strings in which q (q is a natural number) data units being p-bit (p is a natural number equal to two or above) data, includes a unit configured to predict a parity value of a first data unit from lower order in a result data string representing the multiplication result based on a value and a parity value of a first data unit from lower order in each of the two data strings; and a unit configured to predict a parity value for data at a high-order p?1 bit of the result data string based on a value and a parity value for a q-th data unit from lower order in each of the two data strings.