2156-91-4 Usage
Check Digit Verification of cas no
The CAS Registry Mumber 2156-91-4 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 2,1,5 and 6 respectively; the second part has 2 digits, 9 and 1 respectively.
Calculate Digit Verification of CAS Registry Number 2156-91:
(6*2)+(5*1)+(4*5)+(3*6)+(2*9)+(1*1)=74
74 % 10 = 4
So 2156-91-4 is a valid CAS Registry Number.