286 is the natural number following 285 and preceding 287.
In mathematics
- 286 is an even composite number with 3 prime factors.[1]
- 286 is in the smallest pair of nontotient anagrams with 268.[2]
- 286 is a tetrahedral number which means that represents a tetrahedron.[3]
- 286 is a sphenic number which means that it has exactly 3 prime factors.[4]
- 286 the first even pseudoprime to base 3.[5]
References
- ^ "Composite numbers". mathworld.wolfram.com.
- ^ Sloane, N. J. A. (ed.). "Sequence A039772 (Even numbers k such that phi(k) and k-1 are distinct and have a common factor > 1)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
- ^ "Tetrahedral numbers". mathworld.wolfram.com.
- ^ "Sphenic numbers". mathworld.wolfram.com.
- ^ Sloane, N. J. A. (ed.). "Sequence A130433 (Even pseudoprimes to base 3)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.