FACTBOX: Russian president and PM: who does what?

(Reuters) - Dmitry Medvedev is set to win Russia's presidential election by a huge margin to succeed Vladimir Putin, first official results from the Central Election Commission showed on Sunday.

But Putin, by far the most popular politician, will retain considerable influence as prime minister under his protege.

Medvedev himself has expressed confidence this power-sharing arrangement -- unusual for Russia -- will work. Skeptics say the partnership is bound to self-destruct and forsee differences in terms of handling problems and prioritizing reforms.

Following is a breakdown of presidential and prime ministerial powers under the current constitutional rules.

Political analysts caution that an exclusively legal view of the division of power does not allow for the deeply personal basis of authority in Russia.

* PRESIDENT:

- Head of state.

- Office is in the Kremlin.

- Commander-in-chief of armed forces -- in charge of Russia's nuclear weapons.

- Sets direction of foreign and domestic policies.

- Guarantor of the constitution, citizens' rights.

- Defender of Russia's sovereignty.

- Prime minister reports directly to the president.

- Appoints and sacks PM and other federal ministers, subject to parliamentary approval.

- All Russian spy services report directly to the president.

- Foreign Ministry, Defence Ministry, Interior Ministry, Emergency Ministry, Justice Ministry report directly to president.