15778
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 28
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 28800
- Proper Divisor Sum (Aliquot Sum)
- 13022
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6468
- Möbius Function
- 0
- Radical
- 322
- Omega Function (Ω)
- 5
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 102
- Smith Number
- yes
- 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
- Least Smith number having digital sum A033662(n).at n=15A033663
- Number of partitions of n into parts not of the form 9k, 9k+2 or 9k-2. Also number of partitions with 1 part of size 1 and differences between parts at distance 3 are greater than 1.at n=48A035941
- Numbers whose base-5 representation contains exactly three 0's and three 1's.at n=26A045172
- Generalized Stirling number triangle of first kind.at n=33A051186
- Numbers k such that 279*2^k + 1 is prime.at n=21A053356
- Numbers k such that (7*3^k - 5)/2 is prime.at n=21A059569
- Number of permutations satisfying -k <= p(i) - i <= r and p(i) - i not in I, i=1..n, with k=1, r=4, I={0,3}.at n=30A079973
- Expansion of x^9/((1-x)*(1-x^2)*(1-x^3))^2.at n=31A117485
- Degree of denominator of GF for number of ways to place k nonattacking queens on an n X n toroidal board.at n=10A178720
- Numbers n such that n!10-1 is prime.at n=31A204658
- a(n) = (a(n-1) - a(n-3))*7^((1+(-1)^n)/2) with a(6)=5, a(7)=4, a(8)=22.at n=13A215139
- Number of n X 6 0..1 arrays with row sums nondecreasing and column sums unimodal.at n=2A223624
- T(n,k)=Number of nXk 0..1 arrays with row sums nondecreasing and column sums unimodal.at n=30A223625
- Number of 3Xn 0..1 arrays with row sums nondecreasing and column sums unimodal.at n=5A223627
- Number of partitions p of n such that (number of numbers of the form 3k+2 in p) is a part of p.at n=37A241548
- Number of compositions (ordered partitions) of n into prime divisors of n.at n=30A284463
- Number of compositions (ordered partitions) of n into prime power divisors of n (not including 1).at n=30A284465
- Fully multiplicative with a(prime(k)) = Lucas(2*(k+1)) for k-th prime p, where Lucas(n) = A000032(n).at n=43A324900
- Numbers that are the sum of four positive cubes in exactly five ways.at n=39A343986
- Number of partitions of n whose greatest part is a multiple of 4.at n=43A363046