12558
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 32
- Divisor Sum
- 32256
- Proper Divisor Sum (Aliquot Sum)
- 19698
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 3168
- Möbius Function
- -1
- Radical
- 12558
- Omega Function (Ω)
- 5
- Little Omega Function (ω)
- 5
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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 107
- Smith Number
- yes
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
- Numbers k such that the least term in the periodic part of the continued fraction for sqrt(k) is 16.at n=13A031694
- Products of exactly 5 distinct primes.at n=34A046387
- Numbers k that divide the number of partitions of k into distinct parts (A000009).at n=14A056848
- Number of basis partitions (or basic partitions) of n.at n=51A066447
- Triangle read by rows: T(n,k) gives number of ways of arranging n chords on a circle with k simple intersections (i.e., no intersections with 3 or more chords) - positive values only.at n=51A067311
- Numbers n such that sopf(phi(n)) = phi(sopf(n)), where sopf(x) = sum of the distinct prime factors of x.at n=39A076531
- The (1,1)-entry of the matrix A^n, where A = [0,1;2,3].at n=8A106434
- G.f. satisfies: 4*A(x) = 3 + x + A(x)^3, starting with [1,1,3].at n=6A120590
- Indices of products of twin primes in the semiprimes.at n=15A131188
- 3 times 13-gonal (or tridecagonal) numbers: a(n) = 3*n*(11*n - 9)/2.at n=28A153875
- a(n) = 256*n^2 + 2*n.at n=6A158230
- a(n) = 196*n^2 + 14.at n=8A158555
- Numbers n such that n^6 + 545 is prime.at n=5A163592
- (1,[99n+1]) Pascal Triangle.at n=51A172179
- Coefficient triangle of the denominators of the (n-th convergents to) the continued fraction 1/(w+2/(w+3/(w+4/... . Conjectured to equal unsigned version of A137286.at n=71A180048
- T(n,k) = Stirling2(n,k) * OrderedBell(k).at n=30A232598
- Triangle read by rows, T(n,k) = {n,k}*h(k), where {n,k} are the Stirling set numbers and h(k) = hypergeom([-k+1,-k],[],1), for n>=0 and 0<=k<=n.at n=39A256549
- Alternating sum of 10-gonal (or decagonal) pyramidal numbers.at n=26A269441
- Numbers k such that (68*10^k + 7)/3 is prime.at n=27A270613
- Numbers n such that (2^n + 1) / gcd(n, 2^n + 1) is not squarefree.at n=34A272361