8239
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
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 10368
- Proper Divisor Sum (Aliquot Sum)
- 2129
- 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
- 6360
- Möbius Function
- -1
- Radical
- 8239
- 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
- 158
- 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
- Eight iterations of Reverse and Add are needed to reach a palindrome.at n=22A015988
- Fibonacci sequence beginning 3, 20.at n=14A022129
- a(n) = s(1)*s(n) + s(2)*s(n-1) + ... + s(k)*s(n+1-k), where k = floor((n+1)/2), s = (natural numbers >= 3).at n=40A024312
- a(n+1) = [ A*a(n)+B ]/p^r, where p^r is the highest power of p diving [ A*a(n)+B ] and p=2, A=2.00013, B=3.0.at n=36A029580
- Triangle T(n,k) giving number of 4 X k polyominoes with n cells (n >= 4, 1<=k<=n-3).at n=42A059684
- Numbers which need eight 'Reverse and Add' steps to reach a palindrome.at n=17A065213
- a(n)= Sum_{j=0..floor(n/2)} A073145(2*j + q), where q = 2*(n/2 - floor(n/2)).at n=29A074585
- 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, -1, 1), (0, 0, -1), (0, 1, -1), (1, 1, 0)}.at n=9A148674
- 7 times heptagonal numbers: a(n) = 7*n*(5*n-3)/2.at n=22A152777
- Products of 3 distinct safe primes.at n=21A157354
- a(n) = 3*a(n-1) + 2^n - 6, with a(1) = 3.at n=7A169650
- Number of 0..6 arrays x(0..n+1) of n+2 elements without any two consecutive increases or two consecutive decreases.at n=2A200836
- T(n,k)=Number of 0..k arrays x(0..n+1) of n+2 elements without any two consecutive increases or two consecutive decreases.at n=30A200838
- Number of 0..n arrays x(0..4) of 5 elements without any two consecutive increases or two consecutive decreases.at n=5A200840
- Start of a triple of consecutive squarefree numbers each of which has exactly 3 distinct prime factors.at n=52A242606
- Number of (n+2) X (1+2) 0..1 arrays with no 3 x 3 subblock diagonal sum 0 and no antidiagonal sum 0 and no row sum 2 and no column sum 2.at n=17A255221
- Partial sums of A073602.at n=27A259035
- Number of orbits of Aut(Z^7) as function of the infinity norm n of the representative lattice point of the orbit, when the cardinality of the orbit is equal to 26880.at n=22A266397
- Position of the first time an n-digit number appears twice in a row after the decimal point of Pi.at n=3A287994
- Numbers whose trajectories under the map x -> A230625(x) never reach a prime.at n=36A288847