Short answers, pulled from the story.
Russia uses telephone country code 7, which it shares with Kazakhstan. Country code 7 was originally assigned to the Soviet Union and continued to be used by Russia and Kazakhstan after the other thirteen successor states switched to new codes between 1993 and 1998.
All Russian national significant numbers assigned to subscriber telephones contain exactly ten digits. The number consists of a three-digit area code and a seven-digit subscriber number, which includes a zone code of up to two digits.
Moscow City uses area codes 495 and 499, replacing the old code 095 which expired on the 31st of January 2006. Moscow Oblast uses codes 496 and 498.
Abkhazia switched to the Russian numbering plan on the 1st of January 2010. The change followed a Memorandum of Cooperation signed between Russia and Abkhazia on the 28th of September 2009, after Russia recognized Abkhazia's independence.
The Republic of Crimea received area code 365 and Sevastopol received 869 following the 2014 annexation. On the 7th of May 2022, Donetsk received 856, Luhansk received 857, Kherson received 860, and Zaporozhye received 810.
Russia uses 112 as its general emergency number. Individual services also have three-digit codes: 101 for the fire brigade, 102 for police, 103 for ambulance, and 104 for gas service. The older single-digit codes 01 through 04 remain active in parallel.