The CAS Registry Mumber 130457-98-6 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,3,0,4,5 and 7 respectively; the second part has 2 digits, 9 and 8 respectively. Calculate Digit Verification of CAS Registry Number 130457-98: (8*1)+(7*3)+(6*0)+(5*4)+(4*5)+(3*7)+(2*9)+(1*8)=116 116 % 10 = 6 So 130457-98-6 is a valid CAS Registry Number.