The 7572 on Dayi Qizi cake is called "mark number", which you can understand as a commodity name.

These four numbers are not written casually. The first two digits 75 represent that the formula of this product was successfully developed in 1975. The number 7 in the third place represents that the average grade of raw materials is 7; The fourth representative factory (Yunnan Native Products Company has four directly affiliated state-owned factories, 1 Kunming factory, 2 Menghai factory, 3 Shimonoseki factory and 4 Puxiu factory).