1660
1660 is the year the Royal Society was founded and the English monarchy restored.
- Even
- Composite
Where 1660 fits
Why 1660 is special
The Society's motto, roughly 'take nobody's word for it', set out the principle that claims must be demonstrated rather than asserted. It is the oldest continuously existing scientific academy.
Same number, different meanings
How 1660 is understood across different contexts — never implying one meaning because of another.
- Mathematics
The Society's motto, roughly 'take nobody's word for it', set out the principle that claims must be demonstrated rather than asserted. It is the oldest continuously existing scientific academy.
- History
In 1660, the monarchy was restored under Charles II, and the Royal Society was founded (England).
- Science
The Royal Society's founding motto made verification rather than authority the test of a claim. It is a plain statement of what separates the scientific method from what preceded it, and it dates from the same year England restored its monarchy.
1660 is part of
Factors & digit properties
- Divisors (12)
- 1, 2, 4, 5, 10, 20, 83, 166, 332, 415, 830, 1660
- Prime factorisation
- 2^2 × 5 × 83
- Digit sum
- 13
- Digital root
- 4
Representations
- Decimal
- 1660
- Scientific notation
- 1.660 × 10^3
Roman numerals
M D C L X
Binary
1 1 0 0 1 1 1 1 1 0 0
1 × 1,024 + 1 × 512 + 0 × 256 + 0 × 128 + 1 × 64 + 1 × 32 + 1 × 16 + 1 × 8 + 1 × 4 + 0 × 2 + 0 × 1 = 1,660
Octal
3 1 7 4
3 × 512 + 1 × 64 + 7 × 8 + 4 × 1 = 1,660
Hexadecimal
6 7 c
6 × 256 + 7 × 16 + c × 1 = 1,660
Read as powers of two: 1,024 + 512 + 64 + 32 + 16 + 8 + 4 = 1,660.
In historical numeral systems
Egyptian
1 lotus, 6 coils of rope, 6 hobbles
1 × 1,000 + 6 × 100 + 6 × 10 = 1,660. 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), 4 corner wedges (units place)
27 × 60 + 40 = 1660. 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
Related numbers & connections
1660 is a year in the 17th century, in the 1660s.
Cromwell died in 1658 and the monarchy returned in 1660. A republic founded on removing a hereditary ruler could not manage a hereditary succession.
View 1658 →History
In 1660, the monarchy was restored under Charles II, and the Royal Society was founded (England).
DocumentedHistoryGeography: EnglandPeriod: 1660
Science
The Royal Society's founding motto made verification rather than authority the test of a claim. It is a plain statement of what separates the scientific method from what preceded it, and it dates from the same year England restored its monarchy.
DocumentedScienceGeography: EnglandPeriod: 1660
Common questions
Is 1660 a prime number?
No, 1660 is not prime.
What are the factors of 1660?
The factors of 1660 are 1, 2, 4, 5, 10, 20, 83, 166, 332, 415, 830, 1660.
What is 1660 in Roman numerals?
1660 in Roman numerals is MDCLX.
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