Liver 19cm in length with normal density. is this a good thing??

It is within normal: The average dimensions of liver in an adult male is: length 26.4±0.1 (CM); width: 15.7±0.2 (cm); depth: 6.0±0.2 (cm). The average weight is between 1500 and 1700 gm. For a female, the respective measurements are: length: 25.4±0.2; width: 15.0±0.1; depth: 5.5±0.2 and weight is 1200-1500 gm. So you are fine, assuming all your blood work is fine and there is no reason for you to have liver disease