8959
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 31
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 9824
- Proper Divisor Sum (Aliquot Sum)
- 865
- 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
- 8160
- Möbius Function
- 0
- Radical
- 527
- 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
- no
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 246
- 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
- Smallest multiple of n whose digits sum to n.at n=31A002998
- a(n) = (2*n - 3)n^2.at n=17A015238
- Eight iterations of Reverse and Add are needed to reach a palindrome.at n=30A015988
- Numbers k such that the continued fraction for sqrt(k) has period 68.at n=32A020407
- Numbers k that divide the (left) concatenation of all numbers <= k written in base 18 (most significant digit on left).at n=8A029487
- 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 93.at n=26A031591
- Divide odd numbers into groups with prime(n) elements and add together.at n=10A034960
- Numbers whose base-4 representation contains exactly two 2's and four 3's.at n=30A045147
- Smallest number m larger than prime(n) such that prime(n) = sum of digits of m and prime(n) = largest prime factor of m (or 0 if no such number exists).at n=9A052022
- T(n,n-4), where T is the array in A055830.at n=33A055831
- Solutions (value of x) of Diophantine equation 2*x^2 + 3*x + 2 = r^2.at n=5A056161
- Numbers which need eight 'Reverse and Add' steps to reach a palindrome.at n=25A065213
- Smallest proper multiple of n with digit sum n.at n=30A069035
- Numbers n such that sum of digits of n equals the squarefree part of n.at n=47A070274
- Smallest multiple of n with two or more digits, none of them zeros, whose digit sum equals n, or 0 if no such multiple exists.at n=30A077754
- n-th positive integer whose digits sum up to n.at n=30A081927
- Numerator of n-th term of the harmonic series after removal of all terms 1/m from Sum_{m=1..n} 1/m for which m contains a 9 in its decimal representation.at n=9A111935
- A sequence of asymptotic density zeta(9) - 1, where zeta is the Riemann zeta function.at n=17A143035
- a(n) = 256*n - 1.at n=34A158250
- a(n) is the smallest number which is divisible by n, is not equal to n and its digital sum is also divisible by n.at n=30A163502