5245
RFC 5245 was the original ICE specification.
- Odd
- Composite
Where 5245 fits
Why 5245 is special
It was replaced after a decade because its aggressive nomination mode proved unnecessary and its state machine was widely misimplemented.
5245 is part of
Factors & digit properties
- Divisors (4)
- 1, 5, 1049, 5245
- Prime factorisation
- 5 × 1049
- Digit sum
- 16
- Digital root
- 7
Representations
- Decimal
- 5245
- Scientific notation
- 5.245 × 10^3
Roman numerals
Roman numerals as modelled here goes up to 3,999.
Binary
1 0 1 0 0 0 1 1 1 1 1 0 1
1 × 4,096 + 0 × 2,048 + 1 × 1,024 + 0 × 512 + 0 × 256 + 0 × 128 + 1 × 64 + 1 × 32 + 1 × 16 + 1 × 8 + 1 × 4 + 0 × 2 + 1 × 1 = 5,245
Octal
1 2 1 7 5
1 × 4,096 + 2 × 512 + 1 × 64 + 7 × 8 + 5 × 1 = 5,245
Hexadecimal
1 4 7 d
1 × 4,096 + 4 × 256 + 7 × 16 + d × 1 = 5,245
Read as powers of two: 4,096 + 1,024 + 64 + 32 + 16 + 8 + 4 + 1 = 5,245.
In historical numeral systems
Egyptian
5 lotuses, 2 coils of rope, 4 hobbles, 5 strokes
5 × 1,000 + 2 × 100 + 4 × 10 + 5 × 1 = 5,245. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
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
- Happy number
- Semiprime
Related numbers & connections
ICE was respecified after its original state machine proved too complicated to implement consistently.
View 8445 →Technology & computing
RFC 5245 specified the first version of ICE. It was obsoleted by RFC 8445, which removed aggressive nomination and simplified the checking procedure.
DocumentedTechnology & computingGeography: International — IETFPeriod: 2010
Common questions
Is 5245 a prime number?
No, 5245 is not prime.
What are the factors of 5245?
The factors of 5245 are 1, 5, 1049, 5245.
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