440 (four hundred [and] forty) is the natural number following 439 and preceding 441.
In mathematics
440 has the factorization 23 · 5 · 11.
440 is:
- Even
- The sum of the first 17 prime numbers
- A harshad number
- An abundant number[1]
- A happy number[2]
In science
- A440 (pitch standard) widely used for the musical note A4, the A above Middle C, often used for tuning instruments
References
- ^ "Facts about the number 440". Numbermatics - the number explorer. Retrieved 21 March 2017.
- ^ Guy, Richard (9 March 2013). Unsolved Problems in Number Theory. Springer Science & Business Media. p. 358. ISBN 9780387266770.