2620
2,620 and 2,924 are the third-smallest amicable pair.
- Even
- Composite
Where 2620 fits
Why 2620 is special
Euler found dozens of pairs in the eighteenth century, transforming a subject that had produced three examples in two thousand years into one with a general method.
2620 is part of
Factors & digit properties
- Divisors (12)
- 1, 2, 4, 5, 10, 20, 131, 262, 524, 655, 1310, 2620
- Prime factorisation
- 2^2 × 5 × 131
- Digit sum
- 10
- Digital root
- 1
Representations
- Decimal
- 2620
- Scientific notation
- 2.620 × 10^3
Roman numerals
M M D C X X
Binary
1 0 1 0 0 0 1 1 1 1 0 0
1 × 2,048 + 0 × 1,024 + 1 × 512 + 0 × 256 + 0 × 128 + 0 × 64 + 1 × 32 + 1 × 16 + 1 × 8 + 1 × 4 + 0 × 2 + 0 × 1 = 2,620
Octal
5 0 7 4
5 × 512 + 0 × 64 + 7 × 8 + 4 × 1 = 2,620
Hexadecimal
a 3 c
a × 256 + 3 × 16 + c × 1 = 2,620
Read as powers of two: 2,048 + 512 + 32 + 16 + 8 + 4 = 2,620.
In historical numeral systems
Egyptian
2 lotuses, 6 coils of rope, 2 hobbles
2 × 1,000 + 6 × 100 + 2 × 10 = 2,620. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
4 corner wedges + 3 vertical wedges (sixties place), 4 corner wedges (units place)
43 × 60 + 40 = 2620. 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
- Happy number
- Harshad (Niven) number
Mathematics
Before Euler, three amicable pairs were known in total. He published around sixty, which changed the subject from a collection of curiosities into something with a method behind it.
DocumentedMathematics
Common questions
Is 2620 a prime number?
No, 2620 is not prime.
What are the factors of 2620?
The factors of 2620 are 1, 2, 4, 5, 10, 20, 131, 262, 524, 655, 1310, 2620.
What is 2620 in Roman numerals?
2620 in Roman numerals is MMDCXX.
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