1779
1779 is the year the first cast-iron bridge was built.
- Odd
- Composite
Where 1779 fits
Why 1779 is special
The Iron Bridge at Coalbrookdale used iron where builders knew only timber and stone, so it was assembled with carpentry joints — dovetails and mortises cut into metal. It still stands.
1779 is part of
Factors & digit properties
- Divisors (4)
- 1, 3, 593, 1779
- Prime factorisation
- 3 × 593
- Digit sum
- 24
- Digital root
- 6
Representations
- Decimal
- 1779
- Scientific notation
- 1.779 × 10^3
Roman numerals
M D C C L X X I X
MDCCLXXIX uses the subtractive pair IX: one before ten — ten minus one.
Binary
1 1 0 1 1 1 1 0 0 1 1
1 × 1,024 + 1 × 512 + 0 × 256 + 1 × 128 + 1 × 64 + 1 × 32 + 1 × 16 + 0 × 8 + 0 × 4 + 1 × 2 + 1 × 1 = 1,779
Octal
3 3 6 3
3 × 512 + 3 × 64 + 6 × 8 + 3 × 1 = 1,779
Hexadecimal
6 f 3
6 × 256 + f × 16 + 3 × 1 = 1,779
Read as powers of two: 1,024 + 512 + 128 + 64 + 32 + 16 + 2 + 1 = 1,779.
In historical numeral systems
Egyptian
1 lotus, 7 coils of rope, 7 hobbles, 9 strokes
1 × 1,000 + 7 × 100 + 7 × 10 + 9 × 1 = 1,779. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
2 corner wedges + 9 vertical wedges (sixties place), 3 corner wedges + 9 vertical wedges (units place)
29 × 60 + 39 = 1779. Places are separated by a space on the tablet, with the higher place written first.
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
- Deficient number
- Semiprime
Related numbers & connections
1779 is a year in the 18th century, in the 1770s.
Coke smelting from 1709 made iron cheap enough that the first cast-iron bridge could be built at Coalbrookdale in 1779, assembled with carpentry joints because nobody knew how else to join structural iron.
View 1709 →Numbers Around Us
- appears inHistorical years
why?
Strength 0.50, confidence "high".
Other connections
- developed from1709
why?
Strength 0.50, confidence "high".
Technology & computing
In 1779, the Iron Bridge at Coalbrookdale was erected, the first large bridge built of cast iron (England).
DocumentedTechnology & computingGeography: EnglandPeriod: 1779The Iron Bridge's builders had no precedent for joining structural iron, so they used woodworking joints scaled up in metal. The result was heavier than necessary and has survived nearly 250 years.
DocumentedTechnology & computingGeography: EnglandPeriod: 1779
Common questions
Is 1779 a prime number?
No, 1779 is not prime.
What are the factors of 1779?
The factors of 1779 are 1, 3, 593, 1779.
What is 1779 in Roman numerals?
1779 in Roman numerals is MDCCLXXIX. IX is subtractive: one before ten — ten minus one. Written additively it would be MDCCLXXVIIII, which Roman inscriptions used freely — the strict subtractive form is a later convention.
About this page's data
Mathematical facts:computed directly from the number's value — nothing to source or verify externally.
Contextual records: 2 reviewer-confirmed records, sourced and reviewed before publication.
Last reviewed: 15 July 2026