1366
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 2052
- Proper Divisor Sum (Aliquot Sum)
- 686
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 682
- Möbius Function
- 1
- Radical
- 1366
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
Special
- Factorial
- no
- Catalan Number
- no
- Bell Number
- no
- Motzkin Number
- no
- Primorial
- no
Figurate Numbers
- Fibonacci Number
- no
- Triangular Number
- no
- Perfect Square
- no
- Perfect Cube
- no
- Pentagonal Number
- no
- Hexagonal Number
- no
- Lucas Number
- no
- Tetrahedral Number
- no
- Pell Number
- no
- Tribonacci Number
- no
- Pronic Number
- no
Recreational
- Happy Number
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 39
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- Squarefree Number
- yes
- Prime Power
- no
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- yes
- Odd
- no
Appears in sequences
- a(n) = a(n-1) + a(n-2) - 2, a(0) = 4, a(1) = 3.at n=15A000211
- No-3-in-line problem: number of inequivalent ways of placing 2n points on an n X n grid so that no 3 are in a line.at n=13A000769
- Numbers that are the sum of 3 nonnegative cubes in more than 1 way.at n=7A001239
- Expansion of 1/((1-x)^2*(1-x^2)*(1-x^5)).at n=39A001304
- A Fielder sequence: a(n) = a(n-1) + a(n-2) - a(n-7), n >= 8.at n=15A001636
- Numbers k such that x^k + x + 1 is irreducible over GF(2).at n=22A002475
- Numbers that are the sum of 8 positive 5th powers.at n=50A003353
- a(2*n) = 2*a(2*n-1), a(2*n+1) = 2*a(2*n)-1.at n=12A005578
- Sum of degrees of irreducible representations of alternating group A_n.at n=8A007002
- Number of (marked) cyclic n-bit binary strings containing no runs of length > 2.at n=14A007040
- a(n) = (8^n + 2*(-1)^n)/3.at n=4A007613
- Coordination sequence T3 for Zeolite Code EUO.at n=23A008098
- Coordination sequence T8 for Zeolite Code MFS.at n=23A008180
- Coordination sequence T3 for Zeolite Code TON.at n=23A008243
- Numbers that are the sum of 3 positive cubes in more than one way.at n=2A008917
- "Pascal sweep" for k=8: draw a horizontal line through the 1 at C(k,0) in Pascal's triangle; rotate this line and record the sum of the numbers on it (excluding the initial 1).at n=38A009522
- Values of k at which the period of the continued fraction for sqrt(k) sets a new record.at n=25A013645
- a(n) = a(n-1) + 2*a(n-2) with a(0)=0, a(1)=2.at n=11A014113
- Apply partial sum operator thrice to Stern's sequence.at n=9A014173
- a(1)=1, a(n) = n*21^(n-1) + a(n-1).at n=2A014938