13666
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 20502
- Proper Divisor Sum (Aliquot Sum)
- 6836
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6832
- Möbius Function
- 1
- Radical
- 13666
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 58
- Smith Number
- yes
- 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
- Nonsquare values of m in the discriminant D = 4*m leading to a new maximum of the L-function of the Dirichlet series L(1) = Sum_{k>0} Kronecker(D,k)/k.at n=34A003421
- Coordination sequence for MgNi2, Position Ni2.at n=29A009932
- Positive numbers k such that k and 4*k are anagrams in base 7 (written in base 7).at n=15A023070
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 60 ones.at n=36A031828
- Beastly (or hateful) numbers: numbers containing the string 666 in their decimal expansion.at n=22A051003
- Dimension of the space of weight n cuspidal newforms for Gamma_1( 97 ).at n=35A063370
- Least number whose least prime quadratic nonresidue is prime(n).at n=9A112304
- Egyptian fraction representation for the cube root of 70.at n=2A132544
- Number of length n+3 0..5 arrays with every four consecutive terms having the maximum of some two terms equal to the minimum of the remaining two terms.at n=4A249704
- T(n,k)=Number of length n+3 0..k arrays with every four consecutive terms having the maximum of some two terms equal to the minimum of the remaining two terms.at n=40A249707
- Number of length 5+3 0..n arrays with every four consecutive terms having the maximum of some two terms equal to the minimum of the remaining two terms.at n=4A249711
- Sum of the even parts in the partitions of n into 7 parts.at n=32A309626
- Number of twice-partitions of n with no singletons.at n=17A358828