The CAS Registry Mumber 23486-70-6 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 2,3,4,8 and 6 respectively; the second part has 2 digits, 7 and 0 respectively. Calculate Digit Verification of CAS Registry Number 23486-70: (7*2)+(6*3)+(5*4)+(4*8)+(3*6)+(2*7)+(1*0)=116 116 % 10 = 6 So 23486-70-6 is a valid CAS Registry Number.