1942
1942 is the year the first controlled nuclear chain reaction was achieved.
- Even
- Composite
Where 1942 fits
Why 1942 is special
It ran under the stands of a disused football stadium in Chicago, in a city of three million people, with the only safety measure a man holding an axe beside a rope. The same year, the Beveridge Report laid out the plan for Britain's post-war welfare state.
Same number, different meanings
How 1942 is understood across different contexts — never implying one meaning because of another.
- Mathematics
It ran under the stands of a disused football stadium in Chicago, in a city of three million people, with the only safety measure a man holding an axe beside a rope. The same year, the Beveridge Report laid out the plan for Britain's post-war welfare state.
- History
In 1942, the first controlled nuclear chain reaction was achieved in Chicago (North America).
- Science
The first controlled chain reaction ran beneath the stands of a disused football stadium in a city of three million, with a man holding an axe by a rope as the emergency system. The Beveridge Report, which framed Britain's post-war welfare state, appeared the same year.
1942 is part of
Factors & digit properties
- Divisors (4)
- 1, 2, 971, 1942
- Prime factorisation
- 2 × 971
- Digit sum
- 16
- Digital root
- 7
Representations
- Decimal
- 1942
- Scientific notation
- 1.942 × 10^3
Roman numerals
M C M X L I I
MCMXLII uses the subtractive pair XL: ten before fifty — fifty minus ten.
Binary
1 1 1 1 0 0 1 0 1 1 0
1 × 1,024 + 1 × 512 + 1 × 256 + 1 × 128 + 0 × 64 + 0 × 32 + 1 × 16 + 0 × 8 + 1 × 4 + 1 × 2 + 0 × 1 = 1,942
Octal
3 6 2 6
3 × 512 + 6 × 64 + 2 × 8 + 6 × 1 = 1,942
Hexadecimal
7 9 6
7 × 256 + 9 × 16 + 6 × 1 = 1,942
Read as powers of two: 1,024 + 512 + 256 + 128 + 16 + 4 + 2 = 1,942.
In historical numeral systems
Egyptian
1 lotus, 9 coils of rope, 4 hobbles, 2 strokes
1 × 1,000 + 9 × 100 + 4 × 10 + 2 × 1 = 1,942. 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), 2 corner wedges + 2 vertical wedges (units place)
32 × 60 + 22 = 1942. 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
1942 is a year in the 20th century, in the 1940s.
Fission was discovered in 1938 and the first controlled chain reaction ran in 1942 — four years from an unexplained laboratory result to a working reactor under a stadium.
View 1938 →Numbers Around Us
- appears inHistorical years
why?
Strength 0.50, confidence "high".
Other connections
- is associated with1938
why?
Strength 0.50, confidence "high".
History
In 1942, the first controlled nuclear chain reaction was achieved in Chicago (North America).
DocumentedHistoryGeography: North AmericaPeriod: 1942
Science
The first controlled chain reaction ran beneath the stands of a disused football stadium in a city of three million, with a man holding an axe by a rope as the emergency system. The Beveridge Report, which framed Britain's post-war welfare state, appeared the same year.
DocumentedSciencePeriod: 1942
Common questions
Is 1942 a prime number?
No, 1942 is not prime.
What are the factors of 1942?
The factors of 1942 are 1, 2, 971, 1942.
What is 1942 in Roman numerals?
1942 in Roman numerals is MCMXLII. XL is subtractive: ten before fifty — fifty minus ten. Written additively it would be MDCCCCXXXXII, 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