7146
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 15522
- Proper Divisor Sum (Aliquot Sum)
- 8376
- 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
- 2376
- Möbius Function
- 0
- Radical
- 2382
- 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
- no
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 75
- 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
- Coordination sequence for root lattice B_3.at n=19A022145
- a(n) = n*(11*n+1)/2.at n=36A022269
- Duplicate of A022269.at n=35A026817
- a(n) = 1*T(n,2n) + 2*T(n,2n-1) + ... + (2n+1)*T(n,0), T given by A027926.at n=9A027993
- Number of partitions of n with equal nonzero number of parts congruent to each of 1 and 3 (mod 5).at n=45A035567
- Numbers whose base-4 representation contains exactly four 2's and two 3's.at n=24A045155
- Beginning with 1, minimum value such that gcd(a(2n-1),a(2n)) = 1, gcd(a(2n),a(2n+1))>1 and a(n) > a(n-1).at n=44A091856
- a(n) = n^5 - n^2*(n^2 - 1)/2.at n=6A100242
- Sum of ordered 3 prime sided prime triangles.at n=32A105100
- a(2*n+1) = 5*a(n), a(2*n+2) = 6*a(n) + a(n-1).at n=38A116553
- "666" in bases 7 and higher rewritten in base 10.at n=27A121205
- Least number k such that (k*M(n))^2 + k*M(n) - 1 is prime with M(i)=i-th Mersenne prime.at n=23A121370
- Largest number k for which the n-th prime is the median of the largest prime dividing the first k integers.at n=36A126283
- Triangle T(n,k), 0 <= k <= n, read by rows given by: T(0,0)=1, T(n,k)=0 if k < 0 or if k > n, T(n,0) = T(n-1,1), T(n,k) = T(n-1,k-1) + 3*T(n-1,k) + T(n-1,k+1) for k >= 1.at n=50A126970
- Duplicate of A121370.at n=23A137908
- a(1)=2. For n >=2, a(n) = the least integer >= a(n-1) that is not coprime to both a(n-1)+1 and a(n-1).at n=25A140525
- Triangular sequence defined by T(n, m) = Coefficients(q(x,n) + x^(n-2)*q(1/x,n))/4, where q(x, n) = d^2*P(x, n)/dx^2 and p(x, n)=(x-1)^(n+1)*Sum_{k>=0} ((-1)^(n + 1)*k^n)*x^(k-1).at n=12A154702
- Number of 3-element nondividing subsets of {1, 2, ..., n}.at n=37A187490
- Potential magic constants of 8 X 8 magic squares composed of consecutive primes.at n=15A189188
- Coefficient of x in the reduction of the n-th 2nd-kind Chebyshev polynomial by x^2 -> x+1.at n=8A192236