6852
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 16016
- Proper Divisor Sum (Aliquot Sum)
- 9164
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 2280
- Möbius Function
- 0
- Radical
- 3426
- Omega Function (Ω)
- 4
- 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
- 31
- 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
- Truncated square numbers: 7*n^2 + 4*n + 1.at n=31A005892
- Expansion of Product_{m>=1} (1 + m*q^m)^10.at n=5A022638
- 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 54.at n=35A031552
- Integers n > 879 such that the 'Reverse and Add!' trajectory of n joins the trajectory of 879.at n=35A063052
- Numbers k such that phi(phi(k)) = sum of prime factors of k.at n=11A075863
- a(n) = -a(n-2) + 2*a(n-4) - a(n-10).at n=27A089135
- a(0)=1; a(n) = sigma_1(n) + sigma_3(n).at n=18A092345
- Consider the family of multigraphs enriched by the species of derangements. Sequence gives number of those multigraphs with n labeled edges.at n=7A098624
- Number of products of factorials not exceeding n!.at n=19A101976
- Numbers n with nonzero digits in their decimal representation such that when all numbers formed by inserting the exponentiation symbol between any two digits are added up, the sum is prime.at n=42A113762
- Number of squares on infinite chessboard that a knight can reach in n moves from a fixed square.at n=31A118312
- a(n) = Sum{k=1..n} Fibonacci(floor(n/k)).at n=19A119737
- a(n) = 7*n^2 + 4*n + 1.at n=32A135704
- a(n), a(n+1), a(n+2), for n=5,8,11,... are respectively the numbers of representations of the integers 2^k-2, 2^k, 2^k+2, where k=(n+4)/3, by unordered sums of two odd primes not belonging to A158846.at n=47A158853
- a(n), a(n+1), a(n+2), for n=5,8,11,... are respectively the numbers of representations of the integers 2^k-2, 2^k, 2^k+2, where k=(n+4)/3, by unordered sums of two odd primes not belonging to A158848.at n=41A158857
- Numbers k such that k^3 +-5 are primes.at n=32A176684
- Where record values occur in A180076.at n=51A180081
- Number of ordered triples (w,x,y) with all terms in {-n, ..., -1, 1, ..., n} and 4w + x + y > 0.at n=12A211629
- Triangular array read by rows: row n shows the coefficients of the polynomial u(n) = c(0) + c(1)*x + ... + c(n)*x^(n) which is the numerator of the n-th convergent of the continued fraction [k, k, k, ... ], where k = (x + 1)/(x + 2).at n=40A231774
- Numbers k such that Bernoulli number B_k has denominator 2730.at n=23A249134