13472
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 26586
- Proper Divisor Sum (Aliquot Sum)
- 13114
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6720
- Möbius Function
- 0
- Radical
- 842
- Omega Function (Ω)
- 6
- 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
- 45
- Smith Number
- yes
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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) = floor(2nd elementary symmetric function of Sum_{j=1..k} 1/j, k = 1,2,...,n).at n=45A025212
- Numbers n such that 99*2^n-1 is prime.at n=30A050575
- p such that p^4 + q^4 = r^4 + s^4 = a(n).at n=40A088728
- Number of permissible patterns of primes in a fixed interval of n consecutive integers.at n=35A094660
- Row sums of correlation triangle for (1+x)^3/(1-x).at n=30A115293
- Numbers k such that A007408(k) is prime.at n=25A124877
- G.f. satisfies: A(x) = 1 + x*A(x)^2/A(-x)^2.at n=9A143555
- Number of permutations of 1..n with displacements restricted to {-6,-5,-4,-3,0,1,2}.at n=12A189595
- Expansion of q * psi(-q) * chi(-q^6) * psi(-q^9) / (phi(-q) * phi(-q^18)) in powers of q where phi(), psi(), chi() are Ramanujan theta functions.at n=46A233693
- Multiply a(n-1) by 2 and drop all 0's.at n=33A242350
- Rounded sums of the non-integer cube roots of n, as partitioned by the integer roots: round(Sum_{j=n^3+1..(n+1)^3-1} j^(1/3)).at n=16A248575
- Expansion of f(x, x^5)^3 / (f(-x, -x^5) * f(-x^2, -x^2)^2) in powers of x where f(, ) is Ramanujan's general theta function.at n=15A260150
- Expansion of psi(q^6) * f(-q^12) / (psi(-q) * psi(q^9)) in powers of q where psi(), f() are Ramanujan theta functions.at n=47A261154
- Expansion of f(-x^6)^2 / (phi(-x) * phi(-x^9)) in powers of x where phi(), f() are Ramanujan theta functions.at n=23A261203
- Number of (not necessarily maximal) cliques in the n-polygon diagonal intersection graph.at n=16A300524
- G.f. A(x) satisfies: A(x) = 1/(1 - 2*x*A(x)/(1 - 2*x*A(x)/(1 - 4*x*A(x)/(1 - 4*x*A(x)/(1 - 6*x*A(x)/(1 - 6*x*A(x)/(1 - ...))))))), a continued fraction.at n=5A301833
- Sum of the odd parts in the partitions of n into 10 parts.at n=32A309661
- Number of series-reduced locally nonintersecting rooted trees whose leaves form an integer partition of n.at n=11A316772
- Triangle read by rows: T(n,k) is the number of chiral pairs of cycles of length n (1) with a color pattern of exactly k colors or equivalently (2) partitioned into k nonempty subsets.at n=86A320647
- Numbers k such that 381*2^k+1 is prime.at n=33A323033