7700
Squawk 7700 declares a general emergency.
- Even
- Composite
Where 7700 fits
Why 7700 is special
It grants the aircraft absolute priority over all other traffic. Flight-tracking websites display 7700 automatically, which is why an emergency is often visible to the public before any announcement is made.
7700 is part of
Factors & digit properties
- Divisors (36)
- 1, 2, 4, 5, 7, 10, 11, 14, 20, 22, 25, 28, 35, 44, 50, 55, 70, 77, 100, 110, 140, 154, 175, 220, 275, 308, 350, 385, 550, 700, 770, 1100, 1540, 1925, 3850, 7700
- Prime factorisation
- 2^2 × 5^2 × 7 × 11
- Digit sum
- 14
- Digital root
- 5
Representations
- Decimal
- 7700
- Scientific notation
- 7.700 × 10^3
Roman numerals
Roman numerals as modelled here goes up to 3,999.
Binary
1 1 1 1 0 0 0 0 1 0 1 0 0
1 × 4,096 + 1 × 2,048 + 1 × 1,024 + 1 × 512 + 0 × 256 + 0 × 128 + 0 × 64 + 0 × 32 + 1 × 16 + 0 × 8 + 1 × 4 + 0 × 2 + 0 × 1 = 7,700
Octal
1 7 0 2 4
1 × 4,096 + 7 × 512 + 0 × 64 + 2 × 8 + 4 × 1 = 7,700
Hexadecimal
1 e 1 4
1 × 4,096 + e × 256 + 1 × 16 + 4 × 1 = 7,700
Read as powers of two: 4,096 + 2,048 + 1,024 + 512 + 16 + 4 = 7,700.
In historical numeral systems
Egyptian
7 lotuses, 7 coils of rope
7 × 1,000 + 7 × 100 = 7,700. 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
- Abundant number
- Harshad (Niven) number
Related numbers & connections
A general emergency and a radio failure. Flight-tracking sites display both automatically, which is why an in-flight emergency is often public before any airline statement.
View 7600 →Two ways of declaring an emergency: a satellite-tracked distress beacon, and a transponder code that tells every radar screen in range. One works anywhere on Earth, the other only where radar reaches.
View 406 →Technology & computing
The transponder code an aircraft sets for a general emergency is 7700 (worldwide, ICAO). One of three reserved codes: 7500 for unlawful interference, 7600 for radio failure, 7700 for everything else urgent. They are memorised as seven-five taken alive, seven-six radio nix, seven-seven going to heaven.
DocumentedTechnology & computingGeography: worldwide, ICAO7700 declares a general emergency and grants absolute priority over all other traffic. Public flight-tracking sites display it automatically, which is why an emergency in the air is frequently known to the internet before any airline statement.
DocumentedTechnology & computing
Common questions
Is 7700 a prime number?
No, 7700 is not prime.
What are the factors of 7700?
The factors of 7700 are 1, 2, 4, 5, 7, 10, 11, 14, 20, 22, 25, 28, 35, 44, 50, 55, 70, 77, 100, 110, 140, 154, 175, 220, 275, 308, 350, 385, 550, 700, 770, 1100, 1540, 1925, 3850, 7700.
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