Numberwise

1638

1638 is the year Galileo published his work on motion and materials.

2 confirmed records · 2 sourcesChecked and sourcedHow we qualify claimsReport a correction

Where 1638 fits

Where 1638 fits: Mathematics, History, Related numbersMathematics: Harshad (Niven) number. History: Historical years. Related numbers: 1633.MathematicsHarshad (Niven) numberHistoryHistorical yearsRelated numbers16331638
1638 connects to 3 worlds: mathematics, history, related numbers.

Why 1638 is special

Written under house arrest and smuggled out for printing in the Netherlands, it contains the physics that outlasted the astronomy he was convicted over.

Same number, different meanings

How 1638 is understood across different contexts — never implying one meaning because of another.

1638 is part of

Factors & digit properties

Divisors (24)
1, 2, 3, 6, 7, 9, 13, 14, 18, 21, 26, 39, 42, 63, 78, 91, 117, 126, 182, 234, 273, 546, 819, 1638
Prime factorisation
2 × 3^2 × 7 × 13
Digit sum
18
Digital root
9

Representations

Decimal
1638
Scientific notation
1.638 × 10^3

Roman numerals

M D C X X X V I I I

Binary

1 1 0 0 1 1 0 0 1 1 0

1 × 1,024 + 1 × 512 + 0 × 256 + 0 × 128 + 1 × 64 + 1 × 32 + 0 × 16 + 0 × 8 + 1 × 4 + 1 × 2 + 0 × 1 = 1,638

Octal

3 1 4 6

3 × 512 + 1 × 64 + 4 × 8 + 6 × 1 = 1,638

Hexadecimal

6 6 6

6 × 256 + 6 × 16 + 6 × 1 = 1,638

Read as powers of two: 1,024 + 512 + 64 + 32 + 4 + 2 = 1,638.

In historical numeral systems

Egyptian

1 lotus, 6 coils of rope, 3 hobbles, 8 strokes

1 × 1,000 + 6 × 100 + 3 × 10 + 8 × 1 = 1,638. 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), 1 corner wedge + 8 vertical wedges (units place)

27 × 60 + 18 = 1638. 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

Documented appearance
1638 is a year in the 17th century, in the 1630s.

1638 is a year in the 17th century, in the 1630s.

Connection
Galileo was tried in 1633 and wrote Two New Sciences under house arrest, published abroad in 1638. The physics outlasted the astronomy he was convicted over.

Galileo was tried in 1633 and wrote Two New Sciences under house arrest, published abroad in 1638. The physics outlasted the astronomy he was convicted over.

View 1633

Numbers Around Us

  • appears inHistorical years
    why?

    Strength 0.50, confidence "high".

Other connections

  • developed from1633
    why?

    Strength 0.50, confidence "high".

How is 1638 connected to another number? →

History

  • In 1638, Galileo published Two New Sciences, setting out the mathematics of motion and material strength (Italy).

    DocumentedHistoryGeography: ItalyPeriod: 1638

Science

  • Galileo's Two New Sciences was composed while confined and printed abroad because publication in Italy was barred. It is the work that founded the study of motion, and it exists because the ban was evaded.

    DocumentedScienceGeography: Italy and NetherlandsPeriod: 1638

Common questions

Is 1638 a prime number?

No, 1638 is not prime.

What are the factors of 1638?

The factors of 1638 are 1, 2, 3, 6, 7, 9, 13, 14, 18, 21, 26, 39, 42, 63, 78, 91, 117, 126, 182, 234, 273, 546, 819, 1638.

What is 1638 in Roman numerals?

1638 in Roman numerals is MDCXXXVIII.

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