855
+855 is the international calling code for Cambodia.
- Odd
- Composite
Where 855 fits
Why 855 is special
Cambodia's fixed-line network was almost entirely destroyed in the 1970s, so the country moved to mobile earlier and more completely than most.
Factors & digit properties
- Divisors (12)
- 1, 3, 5, 9, 15, 19, 45, 57, 95, 171, 285, 855
- Prime factorisation
- 3^2 × 5 × 19
- Digit sum
- 18
- Digital root
- 9
Representations
- Decimal
- 855
- Scientific notation
- 8.550 × 10^2
Roman numerals
D C C C L V
Binary
1 1 0 1 0 1 0 1 1 1
1 × 512 + 1 × 256 + 0 × 128 + 1 × 64 + 0 × 32 + 1 × 16 + 0 × 8 + 1 × 4 + 1 × 2 + 1 × 1 = 855
Octal
1 5 2 7
1 × 512 + 5 × 64 + 2 × 8 + 7 × 1 = 855
Hexadecimal
3 5 7
3 × 256 + 5 × 16 + 7 × 1 = 855
Read as powers of two: 512 + 256 + 64 + 16 + 4 + 2 + 1 = 855.
In historical numeral systems
Egyptian
8 coils of rope, 5 hobbles, 5 strokes
8 × 100 + 5 × 10 + 5 × 1 = 855. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
1 corner wedge + 4 vertical wedges (sixties place), 1 corner wedge + 5 vertical wedges (units place)
14 × 60 + 15 = 855. Places are separated by a space on the tablet, with the higher place written first.
Greek (Ionic)
omega, then nu, then epsilon, marked as a numeral
omega-nu-epsilon + keraia
omega + nu + epsilon 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 tav, then nun, then he
tav-tav-nun-he
tav (400) + tav (400) + nun (50) + he (5) = 855, 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
- Deficient number
- Lucky number (mathematical sieve)
Related numbers & connections
Cambodia and Laos are neighbours whose modern infrastructure was shaped by the same conflict. Laos is the most heavily bombed country per capita in history.
View 856 →Nearby in a sequence
- is adjacent to856
why?
Strength 0.50, confidence "high".
Geography
+855 reaches Cambodia, which skipped much of the fixed-line era because the infrastructure was destroyed, and reached very high mobile penetration as a result.
DocumentedGeographyGeography: Cambodia
Common questions
Is 855 a prime number?
No, 855 is not prime.
What are the factors of 855?
The factors of 855 are 1, 3, 5, 9, 15, 19, 45, 57, 95, 171, 285, 855.
What is 855 in Roman numerals?
855 in Roman numerals is DCCCLV.
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