13969
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
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 14260
- Proper Divisor Sum (Aliquot Sum)
- 291
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 13680
- Möbius Function
- 1
- Radical
- 13969
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 107
- 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
- Expansion of 1/(1-x^3-x^4-x^5-x^6).at n=34A017819
- Sizes of successive balls in D_4 lattice.at n=37A046949
- Numbers x such that sigma(x)-x divides x-1, other than prime powers.at n=7A059047
- Numbers k such that sopf(k) = 2*sopf(k+1), where sopf(k) = A008472.at n=21A064112
- Row sums of triangle A084408.at n=31A084411
- a(n) = Sum_{i=1..n} 2^(b(i) - 1), where b(n) is the differences between consecutive primes.at n=48A086769
- a(n) = (27*n^2 + 9*n + 2)/2.at n=32A093485
- Numbers n such that the sum of the proper divisors of n and n+1 equals either n or n+1.at n=19A130776
- Sum of third powers of three consecutive primes.at n=5A133530
- Semiprime centered triangular numbers.at n=36A184481
- Coefficient of x^2 in minimal polynomial of the continued fraction [1^n,phi,1,1,1,...], where 1^n means n ones and phi = golden ratio = (1 + sqrt(5))/2.at n=10A266707
- Compound filter (sum of proper divisors & prime signature): a(n) = P(A001065(n), A046523(n)), where P(n,k) is sequence A000027 used as a pairing function.at n=59A291765
- a(n) = a(n-1) + a(n-3) + a(n-4), where a(0) = 1, a(1) = 1, a(2) = 4, a(3) = -3.at n=24A295677
- Composite numbers whose sum of aliquot parts divide the sum of the squares of their aliquot parts.at n=32A301482
- Squarefree MM-numbers of strict uniform regular multiset systems spanning an initial interval of positive integers.at n=29A322703
- Side length of a square block of integers, with 1 at the top-left corner, on a diagonally numbered 2D board such that the sum of the integers in the square is a perfect square.at n=4A336186
- Numbers m such that there exist positive integers i <= m and j >= m such that m = Sum_{k=i..j} A001065(k), where A001065(k) = sum of the proper divisors of k, and i and j do not both equal m.at n=19A346140
- Numbers that are the sum of some number of consecutive prime cubes.at n=31A352423
- Numbers k such that A361338(k) = 9.at n=20A361348
- Squarefree semiprimes that are centered triangular numbers.at n=33A380913