Word.ws English Dictionary

repunit

repunit noun: a repdigit consisting only of one or more occurrences of the digit 1.

Noun

repunit (plural repunits)

  1. A repdigit consisting only of one or more occurrences of the digit 1.
    • 11, 111, and 1,111 are repunits.
    • The only known prime repunits are R2, R19, R23, and more recently R317 (discovered by Williams in 1978) and R1031 (discovered by Williams & Dubner in 1986). Moreover, Dubner has determined that for every other prime p less than 10000, the repunit Rp is composite.1991, Paulo Ribenboim, The Little Book of Big Primes, page 172

Forms of repunit

pluralrepunits

Origin of repunit

Blend of rep(eated) + unit.

Questions about repunit

What does repunit mean?
Repunit means a repdigit consisting only of one or more occurrences of the digit 1.
What part of speech is repunit?
Repunit is a noun.
What is the plural of repunit?
The plural of repunit is repunits.

Words near repunit in the dictionary

  1. repunish
  2. repunished
  3. repunishes
  4. repunishing
  5. repunishment
  6. repunit
  7. repunits
  8. repurchase
  9. repurchased
  10. repurchaser
  11. repurchasers

Source and license

Adapted from Wiktionary: repunit (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

Last updated:

Cite this entry: “repunit.” Word.ws, https://word.ws/repunit. Based on Wiktionary, CC BY-SA 4.0.