21501-33-7 Usage
Check Digit Verification of cas no
The CAS Registry Mumber 21501-33-7 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 2,1,5,0 and 1 respectively; the second part has 2 digits, 3 and 3 respectively.
Calculate Digit Verification of CAS Registry Number 21501-33:
(7*2)+(6*1)+(5*5)+(4*0)+(3*1)+(2*3)+(1*3)=57
57 % 10 = 7
So 21501-33-7 is a valid CAS Registry Number.