The CAS Registry Mumber 13464-23-8 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 1,3,4,6 and 4 respectively; the second part has 2 digits, 2 and 3 respectively. Calculate Digit Verification of CAS Registry Number 13464-23: (7*1)+(6*3)+(5*4)+(4*6)+(3*4)+(2*2)+(1*3)=88 88 % 10 = 8 So 13464-23-8 is a valid CAS Registry Number.