8473
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 8740
- Proper Divisor Sum (Aliquot Sum)
- 267
- 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
- 8208
- Möbius Function
- 1
- Radical
- 8473
- Omega Function (Ω)
- 2
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 57
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- 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
- Centered octahedral numbers (crystal ball sequence for cubic lattice).at n=18A001845
- a(n) = C(n,1) + C(n,2) + C(n,3), or n*(n^2 + 5)/6.at n=37A004006
- a(n) = A027113(n, 2n-3).at n=8A027121
- Numbers whose set of base-14 digits is {1,3}.at n=25A032921
- Numbers n > 9 such that x^n + x^9 + x^8 + x^7 + x^6 + x^5 + x^4 + x^3 + x^2 + x +1 is irreducible over GF(2).at n=23A057487
- Number of 3 X 3 matrices, with elements from {0,...,n}, having the property that the middle element of each of the eight 3-element horizontal, vertical and diagonal lines equals the average of the two end elements.at n=36A059329
- Semiprimes p1*p2 such that p2>p1 and p2 mod p1 = 7.at n=41A064905
- Numbers n such that n = pi(n)*k + 1 for some k.at n=27A065136
- Least x = a(n) such that sum of common prime divisors (without multiplicity) of sigma(x) and phi(x) equals n, or 0 if such number (apparently) does not exist.at n=20A082056
- Least x=a(n) such that product of common prime-divisors [without multiplicity] of sigma(x) and phi(x) equals n; or 0 if n is not a squarefree number or if no such x exists. Among indices n only squarefree numbers arise because multiplicity of prime factors is ignored.at n=37A082057
- Triangle of numbers {a(n,k), n >= 0, 0<=k<=n} defined by a(0,0)=1, a(n,0)=a(n-1,n-1), a(n,k)=a(n,k-1) + Sum_{i=0..k-1} a(n-1,i).at n=20A108041
- Triangle of numbers {a(n,k), n >= 0, 0<=k<=n} defined by a(0,0)=1, a(n,0)=a(n-1,n-1), a(n,k)=a(n,k-1) + Sum_{i=0..k-1} a(n-1,i).at n=21A108041
- Leading diagonal of triangle A108041.at n=6A108042
- a(n) = a(n-1) + a(n-2) + a(n-3) - a(n-4); a(0)=0, a(1)=1, a(2)=1, a(3)=1.at n=19A116201
- Sum of the squares of the quadratic residues of prime(n).at n=11A125613
- Start with 3. If a, b in sequence, so is ab+1.at n=28A180432
- Number of permutations p on the set [n] with the properties that abs(p(i)-i) <= 3 for all i, p(1) <= 2, and p(j) >= 2 for j=3,4.at n=10A188498
- Integers n such that for all i > n the largest prime factor of product(i+k, {k,0,8}) exceeds the largest prime factor of product(n+k, {k,0,8}).at n=20A200566
- a(n) = smallest number greater than n, equal to the determinant of the circulant matrix formed by its base-n digits.at n=37A219357
- Number of (n+1)X(1+1) 0..1 arrays x(i,j) with row sums sum{j^3*x(i,j), j=1..1+1} nondecreasing, and column sums sum{i^3*x(i,j), i=1..n+1} nondecreasing.at n=37A232854