8427
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
- 4
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 11452
- Proper Divisor Sum (Aliquot Sum)
- 3025
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5512
- Möbius Function
- 0
- Radical
- 159
- Omega Function (Ω)
- 3
- Little Omega Function (ω)
- 2
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
- 158
- 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
- no
- Odd
- yes
Appears in sequences
- a(n) = a(n-1) + 2*a(n-3).at n=17A003476
- a(n) = a(n-1) + a(n-6), with a(i) = 1 for i = 0..5.at n=39A005708
- Poincaré series [or Poincare series] of Lie algebra associated with a certain braid group.at n=12A007993
- Expansion of 1/(1 - x^6 - x^7 - x^8 - ...).at n=45A017900
- 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 29.at n=38A031527
- Composite numbers whose prime factors contain no digits other than 3 and 5.at n=43A036315
- Numbers that are the product of 3 prime factors whose concatenation is a palindrome.at n=23A046452
- Number of 3-colored generalized Frobenius partitions of n.at n=9A053762
- T(2n+5,n), array T as in A055216.at n=6A055221
- Numbers m such that there are precisely 3 groups of order m.at n=37A055561
- a(n) = smallest k such that the digit sum of 7k is n.at n=37A077494
- 3p^2 where p runs through the primes.at n=15A079705
- Square array T(n,k), read by antidiagonals: number of labeled trees, with increments of labels along edges constrained to +-1, with n nodes that have no label greater than k.at n=61A101477
- a(n) = prime(1^3) + prime(2^3) + prime(3^3) + ... + prime(n^3).at n=7A109789
- a(n) = 196*n - 1.at n=42A158225
- Odd numbers k such that A166100((k-1)/2)/k is not an integer.at n=16A166102
- Number of nontrivial solutions (x,y,z) for each prime number p of the Fermat equation x^p + y^p + z^p = 0 mod (n) where n is prime of the form n = 2p + 1, and x, y, z are integers such that x < = y.at n=8A172426
- Numbers n such that lambda(n) = lambda(n - lambda(n)).at n=59A185165
- Expansion of q^(3/8) * eta(q)^3 / eta(q^3)^4 in powers of q.at n=27A187427
- Expansion of q^(3/8) * a(q) / eta(q^3)^3 in powers of q where a() is a cubic AGM function.at n=27A187429