126
126 miles per hour is the world speed record for steam traction.
- Even
- Composite
Where 126 fits
Why 126 is special
Set by Mallard in 1938, it stands because the attempt damaged the locomotive and because no operator has since had reason to risk equipment for a record with no commercial value.
Factors & digit properties
- Divisors (12)
- 1, 2, 3, 6, 7, 9, 14, 18, 21, 42, 63, 126
- Prime factorisation
- 2 × 3^2 × 7
- Digit sum
- 9
- Digital root
- 9
Representations
- Decimal
- 126
- Scientific notation
- 1.260 × 10^2
Roman numerals
C X X V I
Binary
1 1 1 1 1 1 0
1 × 64 + 1 × 32 + 1 × 16 + 1 × 8 + 1 × 4 + 1 × 2 + 0 × 1 = 126
Octal
1 7 6
1 × 64 + 7 × 8 + 6 × 1 = 126
Hexadecimal
7 e
7 × 16 + e × 1 = 126
Read as powers of two: 64 + 32 + 16 + 8 + 4 + 2 = 126.
In historical numeral systems
Egyptian
1 coil of rope, 2 hobbles, 6 strokes
1 × 100 + 2 × 10 + 6 × 1 = 126. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
2 vertical wedges (sixties place), 6 vertical wedges (units place)
2 × 60 + 6 = 126. Places are separated by a space on the tablet, with the higher place written first.
Greek (Ionic)
rho, then kappa, then stigma, marked as a numeral
rho-kappa-stigma + keraia
rho + kappa + stigma written in descending order and added — the letters carry their values wherever they stand, so this is addition, not place value.
Hebrew numerals
qof, then kaf, then vav
qof-kaf-vav
qof (100) + kaf (20) + vav (6) = 126, written in descending order.
Maya
1 bar + 1 dot (upper, twenties place) over 1 bar + 1 dot (lower, units place)
6 × 20 + 6 = 126. Places stack vertically with the smallest at the bottom, so the upper group is worth twenty times the lower.
Systems that simply cannot reach this value are left out. Where a script needs a font most readers do not have, the reading is given instead of the glyphs — see number systems for each system in full.
Other mathematical patterns
- Abundant number
- Harshad (Niven) number
Related numbers & connections
Mallard reached 126 mph in 1938 and damaged a bearing doing it. The record has stood for nearly ninety years because breaking it would risk an irreplaceable machine for no commercial gain.
View 4468 →Other connections
- is associated with4468
why?
Strength 0.50, confidence "high".
Sport
The steam speed record of 126 mph has stood since 1938. Beating it would require risking an irreplaceable machine for no practical gain, which is why it is effectively permanent.
DocumentedSportGeography: United KingdomPeriod: 1938
Common questions
Is 126 a prime number?
No, 126 is not prime.
What are the factors of 126?
The factors of 126 are 1, 2, 3, 6, 7, 9, 14, 18, 21, 42, 63, 126.
What is 126 in Roman numerals?
126 in Roman numerals is CXXVI.
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: 15 July 2026