17879
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 32
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 18840
- Proper Divisor Sum (Aliquot Sum)
- 961
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 16920
- Möbius Function
- 1
- Radical
- 17879
- 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
- 123
- 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
- Numbers k such that A055079(k) = 2^k.at n=38A057838
- Composite numbers whose divisors (except 1) all contain the digit 9.at n=30A062680
- Numbers k such that reverse(gpf(k)) = gpf(k+1), where gpf(n) = A006530(n); a(1)=1.at n=26A071844
- The n-th highly composite number equals the a(n)-th composite number, for n >= 3.at n=22A074329
- a(n) = 29 + 73*n + 37*n^2.at n=21A145980
- 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, 1), (-1, 1, 0), (0, 0, 1), (1, 0, -1), (1, 1, -1)}.at n=9A148808
- Number of -7..7 arrays x(0..n-1) of n elements with zero sum and no element more than one greater than the previous.at n=6A199846
- Number of -n..n arrays x(0..6) of 7 elements with zero sum and no element more than one greater than the previous.at n=6A199851
- (2^(p-1) modulo p^2) + (3^(p-1) modulo p^2), where p = prime(n).at n=25A240987
- Number of nX4 0..1 arrays with every element equal to 0, 2, 3, 5 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.at n=8A301326
- Number of digraphs on n unlabeled nodes whose strongly connected components are directed cycles.at n=7A361585
- a(n) = numerator(Sum_{k=1..n} d(k+1)/d(k)), where d is the number of divisors function.at n=35A386925