There were two basic types of tank company. Those belonging to the tank battalion of a Motor Rifle Regiment and those belonging to a tank battalion of a tank regiment. In the former case it should be 13 tanks, I company command vehicle and 3X platoons of four vehicles each. For the tank regiment companies were typically ten tank structures. One for the company commander and 3X platoons of three tanks.
There were variations to this, there were independent tank battalions, regiments and some lower readiness divisions might not have managed the four tank platoon in their MRR tank battalions.
Turret numbers? There was no fixed system. Regimental commanders had a degree of latitude in how they implemented the numbering system, which made it harder for NATO to identify organisations.
In general the Soviets used 3 digit codes although there are quite a few examples of four digit codes.
One version was for the first digit to represent the battalion number, the second the company, the third the vehicle number within the company. Ie 237 is 2nd battalion, third company, seventh vehicle.
Another variant, apparently, was to number through the companies within a regiment. First digit being the company within the regiment, second and third identifying the vehicle with the battalion. Ie vehicle number 524 belongs to the fifth company and thus the second battalion ( three companies to each battalion, numbered sequentially through the regiment) and the twenty-fourth vehicle of that battalion.
Hope that helps.