8481
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
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 12384
- Proper Divisor Sum (Aliquot Sum)
- 3903
- 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
- 5120
- Möbius Function
- -1
- Radical
- 8481
- Omega Function (Ω)
- 3
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 109
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- yes
- 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
- Fermat pseudoprimes to base 2, also called Sarrus numbers or Poulet numbers.at n=20A001567
- Number of partitions of 4n-1 into n nonnegative integers each no greater than 8.at n=14A001982
- Euler pseudoprimes: composite numbers n such that 2^((n-1)/2) == +-1 (mod n).at n=13A006970
- Composite numbers k such that k == +-1 (mod 8) and 2^((k-1)/2) == 1 (mod k).at n=10A006971
- Fermat pseudoprimes to base 4.at n=39A020136
- Pseudoprimes to base 17.at n=27A020145
- Numbers whose set of base-16 digits is {1,2}.at n=24A032936
- Multiplicity of highest weight (or singular) vectors associated with character chi_121 of Monster module.at n=37A034509
- Multiplicity of highest weight (or singular) vectors associated with character chi_179 of Monster module.at n=38A034567
- T(n,n-1), array T as in A047060.at n=8A047063
- Euler-Jacobi pseudoprimes: 2^((n-1)/2) == (2 / n) mod n, where (2 / n) is a Jacobi symbol.at n=11A047713
- 18-gonal (or octadecagonal) numbers: a(n) = n*(8*n-7).at n=33A051870
- Geometric mean of the digits = 4. In other words, the product of the digits is = 4^k where k is the number of digits.at n=41A061428
- m for which prime(m) is the least prime dividing #prime(n) - 1, i.e., one less than primorial n-th prime (A057588).at n=14A068489
- Sarrus numbers n (A001567) which satisfy mu(n) = -1 and which are not Super-Poulet numbers (A050217).at n=9A074380
- Sarrus numbers with more than 2 distinct prime factors.at n=9A080747
- Triangle read by rows: T(n,k) is the number of Schroeder paths of length 2n having trapezoid weight k.at n=41A104552
- Odd composite numbers k for which k = A140607((k-1)/2).at n=3A140667
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 0, 1), (-1, 1, 1), (0, 1, -1), (1, 0, 1)}.at n=8A149341
- Sarrus numbers A001567 that are not Carmichael numbers A002997.at n=14A153508