# Mathematician:Ivan Mikheevich Pervushin

## Mathematician

Full name in Russian: **Иван Михеевич Первушин**.

Russian priest, who worked in number theory in his spare time.

Most famous for demonstrating the primality of the Mersenne number $M_{61}$, which then became known as Pervushin's number.

Proved the following:

- 1877: The Fermat number $2^{2^{12}} + 1$ is divisible by $7 \times 2^{14} + 1$, thus showing that $F_{12}$ is not prime
- 1878: The Fermat number $2^{2^{23}} + 1$ is divisible by $5 \times 2^{25} + 1$, thus showing that $F_{23}$ is not prime
- 1883: The Mersenne number $M_{61}$ is a Mersenne prime.

## Nationality

Russian

## History

- Born: January 21, 1827, Lysva, Perm, Russia
- 1852: Graduated from Kazan clerical academy, and became a priest in Zamaraevo.
- 1883: Moved to Shadrinsk, where he wrote a paper ridiculing the local government.
- 1887: Exiled to Mehonskoe as a result.
- Died: June 29, 1900, Mehonskoe, Russia

## Theorems and Definitions

Definitions of concepts named for **Ivan Mikheevich Pervushin** can be found here.