# Mersenne prime

> English word · Noun · IPA /mɛə(ɹ)ˈsɛn ˈpɹaɪm/

## Definitions
1. A prime number which is one less than a power of two (i.e., is expressible in the form 2ⁿ-1; for example, 31=2⁵-1).

## Etymology
Named after French theologian, philosopher, mathematician, and music theorist Marin Mersenne (1588–1648).

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/mersenne-prime