979
979 is the second ISBN prefix, allocated because 978 was running out.
- Odd
- Composite
Where 979 fits
Why 979 is special
Its introduction means the ten-digit form cannot represent every ISBN, so systems that still assume ten digits are silently unable to handle newer books.
979 is part of
Factors & digit properties
- Divisors (4)
- 1, 11, 89, 979
- Prime factorisation
- 11 × 89
- Digit sum
- 25
- Digital root
- 7
Representations
- Decimal
- 979
- Binary
- 1111010011
- Octal
- 1723
- Hexadecimal
- 3d3
- Roman numeral
- CMLXXIX
- Scientific notation
- 9.790 × 10^2
Other mathematical patterns
- Palindromic number
- Deficient number
- Semiprime
- Lucky number (mathematical sieve)
Related numbers & connections
978 and 979 are the two ISBN prefixes. Books issued under 979 have no ten-digit form at all, which quietly breaks systems that still assume one.
View 978 →Other connections
- is associated with978
why?
Strength 0.50, confidence "high".
Technology & computing
Books issued under 979 have no ten-digit equivalent. Any system still storing ISBNs in ten characters cannot represent them, which is a quiet and ongoing data problem in library and retail software.
DocumentedTechnology & computing
Common questions
Is 979 a prime number?
No, 979 is not prime.
What are the factors of 979?
The factors of 979 are 1, 11, 89, 979.
What is 979 in Roman numerals?
979 in Roman numerals is CMLXXIX.
About this page's data
Mathematical facts:computed directly from the number's value — nothing to source or verify externally.
Contextual records: 1 reviewer-confirmed record, sourced and reviewed before publication.
Last reviewed: 3 August 2026