7986
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 30
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 17568
- Proper Divisor Sum (Aliquot Sum)
- 9582
- 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
- 2420
- Möbius Function
- 0
- Radical
- 66
- Omega Function (Ω)
- 5
- 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
- 52
- 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
- Sums of successive Motzkin numbers.at n=11A005554
- Number of 3-voter voting schemes with n linearly ranked choices.at n=20A007009
- Coordination sequence for FeS2-Pyrite, Fe position.at n=41A009957
- Place n distinguishable balls in n boxes (in n^n ways); let f(n,k) = number of ways that max in any box is k, for 1 <= k <= n; sequence gives f(n,n-2)/n.at n=9A019579
- a(n) = n*(n - 1)^3/2.at n=12A019582
- Number of partitions of n in which the least part is even.at n=42A026805
- 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 88.at n=16A031586
- Let F(n) = Q(n) - P(n) be the Fortunate numbers (A005235); sequence gives n such that F(n) = prime(n+1).at n=17A035346
- Numbers k such that phi(k) = phi(k - phi(k)).at n=36A051487
- Numbers n such that n | 10^n + 9^n + 8^n + 7^n + 6^n.at n=35A057252
- Least k such that k*7^n +/- 1 are twin primes.at n=43A064217
- Total sum of squares of parts in all partitions of n.at n=13A066183
- Number of divisors d of n! such that d+1 is prime.at n=19A067847
- Numbers k such that the sum over the prime divisors of k equals the number of divisors of k.at n=29A069234
- Numbers n for which there are exactly six k such that n = k + reverse(k).at n=29A072430
- The terms of A073211 (sums of two powers of 11) divided by 2.at n=13A073219
- G.f.: Product((1+x^i)/(1-x^i),i=1..n-1)/(1-x^n), with n = 5.at n=32A091773
- Numbers of the form (6^i)*(11^j), with i, j >= 0.at n=14A108698
- n-th central term of triangle A118032 divided by n+1 for n>=0, where the matrix square of A118032 forms a diagonal bisection of A118032.at n=12A118039
- a(n) = Product_{k=1..n} D(k), where D() are the doublets, A020338.at n=2A121826