1929
1929 is the year of the Wall Street Crash that opened the Great Depression.
- Odd
- Composite
Where 1929 fits
Why 1929 is special
The crash itself took place over days in October, but the depression that followed was not caused by it alone — banking failures, monetary policy and trade contraction all compounded it. The year is a marker for the start of the slump rather than a full explanation of it.
Same number, different meanings
How 1929 is understood across different contexts — never implying one meaning because of another.
- Mathematics
The crash itself took place over days in October, but the depression that followed was not caused by it alone — banking failures, monetary policy and trade contraction all compounded it. The year is a marker for the start of the slump rather than a full explanation of it.
- History
In 1929, the Wall Street Crash began the Great Depression, and Hubble published evidence that the universe is expanding.
- Finance & economics
The Wall Street Crash took place over several days in October 1929, but the depression that followed had more causes than the crash: bank failures, monetary contraction and collapsing trade all compounded it. Treating 1929 as the explanation rather than the starting marker is the common error.
1929 is part of
Factors & digit properties
- Divisors (4)
- 1, 3, 643, 1929
- Prime factorisation
- 3 × 643
- Digit sum
- 21
- Digital root
- 3
Representations
- Decimal
- 1929
- Scientific notation
- 1.929 × 10^3
Roman numerals
M C M X X I X
MCMXXIX uses the subtractive pair IX: one before ten — ten minus one.
Binary
1 1 1 1 0 0 0 1 0 0 1
1 × 1,024 + 1 × 512 + 1 × 256 + 1 × 128 + 0 × 64 + 0 × 32 + 0 × 16 + 1 × 8 + 0 × 4 + 0 × 2 + 1 × 1 = 1,929
Octal
3 6 1 1
3 × 512 + 6 × 64 + 1 × 8 + 1 × 1 = 1,929
Hexadecimal
7 8 9
7 × 256 + 8 × 16 + 9 × 1 = 1,929
Read as powers of two: 1,024 + 512 + 256 + 128 + 8 + 1 = 1,929.
In historical numeral systems
Egyptian
1 lotus, 9 coils of rope, 2 hobbles, 9 strokes
1 × 1,000 + 9 × 100 + 2 × 10 + 9 × 1 = 1,929. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
3 corner wedges + 2 vertical wedges (sixties place), 9 vertical wedges (units place)
32 × 60 + 9 = 1929. 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
- Happy number
- Semiprime
Related numbers & connections
1929 is a year in the 20th century, in the 1920s.
The 2010 flash crash removed a trillion dollars in minutes and recovered within the hour; the 1929 crash opened a decade-long depression. Speed and consequence are unrelated.
View 2010 →History
In 1929, the Wall Street Crash began the Great Depression, and Hubble published evidence that the universe is expanding.
DocumentedHistoryGeography: globalPeriod: 1929
Finance & economics
The Wall Street Crash took place over several days in October 1929, but the depression that followed had more causes than the crash: bank failures, monetary contraction and collapsing trade all compounded it. Treating 1929 as the explanation rather than the starting marker is the common error.
DocumentedFinance & economicsGeography: United StatesPeriod: 1929
Common questions
Is 1929 a prime number?
No, 1929 is not prime.
What are the factors of 1929?
The factors of 1929 are 1, 3, 643, 1929.
What is 1929 in Roman numerals?
1929 in Roman numerals is MCMXXIX. IX is subtractive: one before ten — ten minus one. Written additively it would be MDCCCCXXVIIII, 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