680
+680 is the international calling code for Palau.
- Even
- Composite
Where 680 fits
Why 680 is special
Palau created the world's first shark sanctuary in 2009 and requires visitors to sign an environmental pledge stamped in their passports.
680 is part of
Factors & digit properties
- Divisors (16)
- 1, 2, 4, 5, 8, 10, 17, 20, 34, 40, 68, 85, 136, 170, 340, 680
- Prime factorisation
- 2^3 × 5 × 17
- Digit sum
- 14
- Digital root
- 5
Representations
- Decimal
- 680
- Scientific notation
- 6.800 × 10^2
Roman numerals
D C L X X X
Binary
1 0 1 0 1 0 1 0 0 0
1 × 512 + 0 × 256 + 1 × 128 + 0 × 64 + 1 × 32 + 0 × 16 + 1 × 8 + 0 × 4 + 0 × 2 + 0 × 1 = 680
Octal
1 2 5 0
1 × 512 + 2 × 64 + 5 × 8 + 0 × 1 = 680
Hexadecimal
2 a 8
2 × 256 + a × 16 + 8 × 1 = 680
Read as powers of two: 512 + 128 + 32 + 8 = 680.
In historical numeral systems
Egyptian
6 coils of rope, 8 hobbles
6 × 100 + 8 × 10 = 680. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
1 corner wedge + 1 vertical wedge (sixties place), 2 corner wedges (units place)
11 × 60 + 20 = 680. Places are separated by a space on the tablet, with the higher place written first.
Greek (Ionic)
chi, then pi, marked as a numeral
chi-pi + keraia
chi + pi written in descending order and added — the letters carry their values wherever they stand, so this is addition, not place value.
Hebrew numerals
tav, then resh, then pe
tav-resh-pe
tav (400) + resh (200) + pe (80) = 680, written in descending order.
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
- Happy number
Related numbers & connections
Palau and the Federated States of Micronesia are both in free association with the United States. Palau created the world's first shark sanctuary in 2009.
View 691 →Other connections
- is associated with691
why?
Strength 0.50, confidence "high".
Geography
+680 reaches Palau, which established the first national shark sanctuary in 2009 and requires arriving visitors to sign a conservation pledge as a condition of entry.
DocumentedGeographyGeography: Palau
Common questions
Is 680 a prime number?
No, 680 is not prime.
What are the factors of 680?
The factors of 680 are 1, 2, 4, 5, 8, 10, 17, 20, 34, 40, 68, 85, 136, 170, 340, 680.
What is 680 in Roman numerals?
680 in Roman numerals is DCLXXX.
About this page's data
Mathematical facts:computed directly from the number's value — nothing to source or verify externally.
Contextual records: 1 reviewer-confirmed record, sourced and reviewed before publication.
Last reviewed: 15 July 2026