129
ISO 129 governs dimensioning on technical drawings.
- Odd
- Composite
Where 129 fits
Why 129 is special
It fixes how a dimension is written and where tolerances go, which is what allows a drawing made in one country to be manufactured in another.
129 is part of
Factors & digit properties
- Divisors (4)
- 1, 3, 43, 129
- Prime factorisation
- 3 × 43
- Digit sum
- 12
- Digital root
- 3
Representations
- Decimal
- 129
- Binary
- 10000001
- Octal
- 201
- Hexadecimal
- 81
- Roman numeral
- CXXIX
- Scientific notation
- 1.290 × 10^2
Other mathematical patterns
- Deficient number
- Happy number
- Semiprime
- Lucky number (mathematical sieve)
Related numbers & connections
General drawing principles come first and dimensioning rules are applied within them.
View 128 →Other connections
- developed from128
why?
Strength 0.50, confidence "high".
Technology & computing
ISO 129 specifies the presentation of dimensions and tolerances on technical product documentation, including arrangement, arrowheads and indication rules.
DocumentedTechnology & computingGeography: International — ISO member bodiesPeriod: 1985–
Common questions
Is 129 a prime number?
No, 129 is not prime.
What are the factors of 129?
The factors of 129 are 1, 3, 43, 129.
What is 129 in Roman numerals?
129 in Roman numerals is CXXIX.
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