The CAS Registry Mumber 24459-59-4 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 2,4,4,5 and 9 respectively; the second part has 2 digits, 5 and 9 respectively. Calculate Digit Verification of CAS Registry Number 24459-59: (7*2)+(6*4)+(5*4)+(4*5)+(3*9)+(2*5)+(1*9)=124 124 % 10 = 4 So 24459-59-4 is a valid CAS Registry Number.