16992
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 27
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 36
- Divisor Sum
- 49140
- Proper Divisor Sum (Aliquot Sum)
- 32148
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5568
- Möbius Function
- 0
- Radical
- 354
- Omega Function (Ω)
- 8
- Little Omega Function (ω)
- 3
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
- 128
- Smith Number
- no
- 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
- From George Gilbert's marks problem: jumping 7 marks at a time (initial positions).at n=22A019997
- Numbers k that divide the (right) concatenation of all numbers <= k written in base 13 (most significant digit on left).at n=39A029458
- COMPOSE natural numbers with primes.at n=6A030281
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 65.at n=27A031563
- Incrementally largest terms in the continued fraction for Euler's constant gamma (A002852).at n=13A033091
- Maximal elements of pairs of "Super Unitary Amicable Numbers", sorted by their minimal elements.at n=28A045614
- a(n) = Sum_{k=0..n} (2^k + Fibonacci(k)).at n=13A101353
- Determinants of 3 X 3 matrices of discrete blocks of 9 consecutive primes.at n=11A117329
- a(n) = 13 + floor(Sum_{j=1..n-1} a(j)/3).at n=25A120157
- Numbers k such that if you subtract k from its reversal you get a positive number with the same digits as k.at n=6A121970
- Degree of the hyperdeterminant of the cubic format (k+1) X (k+1) X (k+1).at n=5A176097
- Numbers p^5*q^2*r where p, q, r are 3 distinct primes.at n=30A179691
- Nonnegative values x of solutions (x, y) to the Diophantine equation x^2 + (x+263)^2 = y^2.at n=8A207058
- Numbers k such that, in the prime factorization of k, the sum of the primes equals the squared sum of exponents.at n=42A231230
- Number of partitions of n such that the number of parts having multiplicity 1 is a part and the number of distinct parts is not a part.at n=41A241444
- Triangle read by rows: T(n,k) = t(n-k, k); t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 8*x + 2.at n=12A257618
- The number of positive integer sequences of length n with no duplicate substrings (forward or backward) of length greater than 1, every number different from its neighbors, and a minimal sum (= A282167(n)).at n=14A284433
- The number of positive integer sequences of length n with no duplicate substrings (forward or backward) of length greater than 1, no self-adjacent terms, and a minimal product (= A282170(n)).at n=14A284436
- Solution (a(n)) of the complementary equation a(n) = 2*a(n-1) - a(n-2) + b(n); see Comments.at n=42A305129
- G.f. = Phi^4, where Phi = g.f. for A028930.at n=33A328529