The CAS Registry Mumber 1318074-58-6 includes 10 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 7 digits, 1,3,1,8,0,7 and 4 respectively; the second part has 2 digits, 5 and 8 respectively. Calculate Digit Verification of CAS Registry Number 1318074-58: (9*1)+(8*3)+(7*1)+(6*8)+(5*0)+(4*7)+(3*4)+(2*5)+(1*8)=146 146 % 10 = 6 So 1318074-58-6 is a valid CAS Registry Number.