You can obtain a Russian visa in the country of your citizenship.

You need to get in touch with the Russian consulate in your country and make sure that your application will be accepted. Conference participants from China, India, DPRK, Japan, etc. can obtain free e-visa on website of the Consular Department of the Ministry of Foreign Affairs of the Russian Federation (https://evisa.kdmid.ru/en-US/Home/Index). 

E-visa is a single-entry visa and issued for 30 calendar days from the date of its issuance. The permitted stay in the Russian Federation with an e-visa is up to 8 days starting from the date of entry, within its validity period.