1656
1656 is the year Huygens built the first pendulum clock.
- Even
- Composite
Where 1656 fits
Why 1656 is special
It cut timekeeping error from about fifteen minutes a day to under a minute. Accurate time is a precondition for most quantitative science that followed.
1656 is part of
Factors & digit properties
- Divisors (24)
- 1, 2, 3, 4, 6, 8, 9, 12, 18, 23, 24, 36, 46, 69, 72, 92, 138, 184, 207, 276, 414, 552, 828, 1656
- Prime factorisation
- 2^3 × 3^2 × 23
- Digit sum
- 18
- Digital root
- 9
Representations
- Decimal
- 1656
- Scientific notation
- 1.656 × 10^3
Roman numerals
M D C L V I
Binary
1 1 0 0 1 1 1 1 0 0 0
1 × 1,024 + 1 × 512 + 0 × 256 + 0 × 128 + 1 × 64 + 1 × 32 + 1 × 16 + 1 × 8 + 0 × 4 + 0 × 2 + 0 × 1 = 1,656
Octal
3 1 7 0
3 × 512 + 1 × 64 + 7 × 8 + 0 × 1 = 1,656
Hexadecimal
6 7 8
6 × 256 + 7 × 16 + 8 × 1 = 1,656
Read as powers of two: 1,024 + 512 + 64 + 32 + 16 + 8 = 1,656.
In historical numeral systems
Egyptian
1 lotus, 6 coils of rope, 5 hobbles, 6 strokes
1 × 1,000 + 6 × 100 + 5 × 10 + 6 × 1 = 1,656. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
2 corner wedges + 7 vertical wedges (sixties place), 3 corner wedges + 6 vertical wedges (units place)
27 × 60 + 36 = 1656. 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
- Abundant number
- Harshad (Niven) number
Related numbers & connections
1656 is a year in the 17th century, in the 1650s.
Early portable timepieces from around 1510 lost hours a day and were worn as jewellery. Accuracy arrived with the pendulum clock in 1656.
View 1510 →Technology & computing
In 1656, Christiaan Huygens built the first pendulum clock, improving timekeeping accuracy by more than an order of magnitude (Low Countries).
DocumentedTechnology & computingGeography: Low CountriesPeriod: 1656The pendulum clock of 1656 improved timekeeping accuracy by more than an order of magnitude at a stroke. Experimental science requiring measured intervals became practical from that point.
DocumentedTechnology & computingGeography: NetherlandsPeriod: 1656
Common questions
Is 1656 a prime number?
No, 1656 is not prime.
What are the factors of 1656?
The factors of 1656 are 1, 2, 3, 4, 6, 8, 9, 12, 18, 23, 24, 36, 46, 69, 72, 92, 138, 184, 207, 276, 414, 552, 828, 1656.
What is 1656 in Roman numerals?
1656 in Roman numerals is MDCLVI.
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