noun · 2 senses · updated from the 2026-07-25 local source snapshot
Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.
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Pronunciation
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/pɹaɪ̯ˈmɔːɹi.əl/
rhymes with -ɔːɹiəl
1
noun
Meaning 1
Any number belonging to the integer sequence whose nth element is the product of the first n primes.
Definition source: English Wiktionary via Wiktextract
Topics: mathematics, number-theory, sciences
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: primorial number
Antonyms: none provided
2
noun
Meaning 2
A unary operation, denoted by the postfix symbol # and defined on the nonnegative integers, which maps 0 to 1, 1 to 1, and each subsequent number to the product of all primes less than or equal to it; the value mapped to by said operation for a given input.
Definition source: English Wiktionary via Wiktextract
Topics: mathematics, number-theory, sciences
Examples
The primorial of 6 is #92;textstyle 6#92;#35;#61;2#92;times 3#92;times 5#61;30.
2020, Rong Pan, Qinheping Hu, Rishabh Singh, Loris D'Antoni, Solving Problem Sketches with Large Integer Values, Peter Müller (editor), Programming Languages and Systems: 29th European Symposium, Proceedings, Springer, LNCS 12075, page 587, The following number theory result relates the primorial to the Chebyshev function. θ(n)= log (n#)= log 2(1+o(n))n=(1+o(n))n
Meaning relationships
Synonyms: none provided
Antonyms: none provided
History
Etymology
Blend of prime + factorial. Coined by American engineer and mathematician Harvey Dubner.
Across languages
Translations
4 source translations are retained for this English entry.