16728
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 24
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 32
- Divisor Sum
- 45360
- Proper Divisor Sum (Aliquot Sum)
- 28632
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5120
- Möbius Function
- 0
- Radical
- 4182
- Omega Function (Ω)
- 6
- Little Omega Function (ω)
- 4
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
- 40
- 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
- yes
- Odd
- no
Appears in sequences
- Unitary-sigma sigma multiply perfect numbers: numbers k such that A061765(k) = m*k for some integer m.at n=35A045795
- Number of certain rooted planar maps.at n=6A046647
- Triangle of rooted planar maps.at n=34A046651
- Values of m such that N = (am+1)(bm+1)(cm+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,57.at n=5A065697
- Triangle read by rows: T(n,k) is the number of nonseparable planar maps with r*n edges and a fixed outer face of r*k edges which are invariant under a rotation of 1/r for any r >= 2 (independent of actual value of r).at n=29A091599
- Largest denominator used in the Egyptian fraction representation of n/(n + 1) by the greedy algorithm.at n=32A100695
- Number of permutations of floor(i*5/3), i=0..n-1, with all sums of two adjacent terms unique.at n=7A147918
- a(n) = Sum_{d|n} phi(n/d)^2*2^d.at n=14A160620
- Numbers k such that sigma(tau(k)) equals the sum of distinct primes dividing k.at n=38A173325
- Molecular topological indices of the Moebius ladders.at n=16A192833
- Molecular topological indices of the prism graphs Y_n.at n=16A192838
- Number of compositions of n where the difference between largest and smallest parts equals 10 and adjacent parts are unequal.at n=15A214279
- Irregular array T(n,k) of the numbers of non-extendable (complete) non-self-adjacent simple paths ending at each of a minimal subset of nodes within a square lattice bounded by rectangles with nodal dimensions n and 5, n >= 2.at n=56A214359
- Irregular array T(n,k) of the numbers of non-extendable (complete) non-self-adjacent simple paths ending at each of a minimal subset of nodes within a square lattice bounded by rectangles with nodal dimensions n and 8, n >= 2.at n=31A214375
- Greatest number (in decimal representation) with n nonprime substrings in base-7 representation (substrings with leading zeros are considered to be nonprime).at n=7A217117
- Number of length 2+2 0..n arrays with the sum of second differences squared multiplied by some arrangement of +-1 equal to zero.at n=24A250321
- (1+e)-sigma amicable numbers.at n=13A274116
- Numbers m such that A049417(A049417(m)) = k*m for some k where A049417 is the infinitary sigma function.at n=16A318182
- Larger of semi-unitary amicable numbers pair: numbers (m, n) such that susigma(m) = susigma(n) = m + n, where susigma(n) is the sum of the semi-unitary divisors of n (A322485).at n=9A322542
- Larger of modified exponential amicable pairs.at n=8A323759