The CAS Registry Mumber 58461-26-0 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 5,8,4,6 and 1 respectively; the second part has 2 digits, 2 and 6 respectively. Calculate Digit Verification of CAS Registry Number 58461-26: (7*5)+(6*8)+(5*4)+(4*6)+(3*1)+(2*2)+(1*6)=140 140 % 10 = 0 So 58461-26-0 is a valid CAS Registry Number.