1961
1961 is the year the Berlin Wall went up and the first human went to space.
- Odd
- Composite
Where 1961 fits
Why 1961 is special
Gagarin orbited in April and construction of the wall began in August. Both were Soviet initiatives in the same year, and each became a lasting symbol of the Cold War for opposite reasons.
1961 is part of
Factors & digit properties
- Divisors (4)
- 1, 37, 53, 1961
- Prime factorisation
- 37 × 53
- Digit sum
- 17
- Digital root
- 8
Representations
- Decimal
- 1961
- Scientific notation
- 1.961 × 10^3
Roman numerals
M C M L X I
MCMLXI uses the subtractive pair CM: a hundred before a thousand — a thousand minus a hundred.
Binary
1 1 1 1 0 1 0 1 0 0 1
1 × 1,024 + 1 × 512 + 1 × 256 + 1 × 128 + 0 × 64 + 1 × 32 + 0 × 16 + 1 × 8 + 0 × 4 + 0 × 2 + 1 × 1 = 1,961
Octal
3 6 5 1
3 × 512 + 6 × 64 + 5 × 8 + 1 × 1 = 1,961
Hexadecimal
7 a 9
7 × 256 + a × 16 + 9 × 1 = 1,961
Read as powers of two: 1,024 + 512 + 256 + 128 + 32 + 8 + 1 = 1,961.
In historical numeral systems
Egyptian
1 lotus, 9 coils of rope, 6 hobbles, 1 stroke
1 × 1,000 + 9 × 100 + 6 × 10 + 1 × 1 = 1,961. 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), 4 corner wedges + 1 vertical wedge (units place)
32 × 60 + 41 = 1961. 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
The Berlin Wall went up in 1961 and the Cuban Missile Crisis followed in October 1962 — the two years in which the Cold War came closest to becoming a war.
View 1962 →Catch-22 was published in 1961 and gave English a term for a rule whose conditions cannot both be met. Heller originally numbered it 18.
View 22 →History
In 1961, Yuri Gagarin became the first human in space.
DocumentedHistoryGeography: globalPeriod: 1961Gagarin orbited Earth in April 1961 and construction of the Berlin Wall began in August. Both were Soviet initiatives within months of each other, and each became a defining Cold War image for opposite reasons.
DocumentedHistoryPeriod: 1961
Common questions
Is 1961 a prime number?
No, 1961 is not prime.
What are the factors of 1961?
The factors of 1961 are 1, 37, 53, 1961.
What is 1961 in Roman numerals?
1961 in Roman numerals is MCMLXI. CM is subtractive: a hundred before a thousand — a thousand minus a hundred. Written additively it would be MDCCCCLXI, 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