15585
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
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 24960
- Proper Divisor Sum (Aliquot Sum)
- 9375
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 8304
- Möbius Function
- -1
- Radical
- 15585
- Omega Function (Ω)
- 3
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 84
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
- a(n) is the least k>1 such that first n terms of Kolakoski sequence A000002 repeat beginning at k-th term.at n=43A022294
- a(n) is the least k>1 such that first n terms of Kolakoski sequence A000002 repeat beginning at k-th term.at n=44A022294
- a(n) is the least k>1 such that first n terms of Kolakoski sequence A000002 repeat beginning at k-th term.at n=45A022294
- a(n) is the least k>1 such that first n terms of Kolakoski sequence A000002 repeat beginning at k-th term.at n=46A022294
- a(n) is the least k>1 such that first n terms of Kolakoski sequence A000002 repeat beginning at k-th term.at n=47A022294
- a(n) is the least k>1 such that first n terms of Kolakoski sequence A000002 repeat beginning at k-th term.at n=48A022294
- a(n) is the least k>1 such that first n terms of Kolakoski sequence A000002 repeat beginning at k-th term.at n=49A022294
- a(n) is the least k>1 such that first n terms of Kolakoski sequence A000002 repeat beginning at k-th term.at n=50A022294
- a(n) is the least k>1 such that first n terms of Kolakoski sequence A000002 repeat beginning at k-th term.at n=51A022294
- a(n) is the least k>1 such that first n terms of Kolakoski sequence A000002 repeat beginning at k-th term.at n=52A022294
- a(n) is the least k>1 such that first n terms of Kolakoski sequence A000002 repeat beginning at k-th term.at n=53A022294
- a(n) is the least k>1 such that first n terms of Kolakoski sequence A000002 repeat beginning at k-th term.at n=54A022294
- a(n) = 2nd elementary symmetric function of the first n+1 positive integers congruent to 1 mod 4.at n=8A024378
- Let R(i,j) be the rectangle with antidiagonals 1; 2,3; 4,5,6; ...; each k is an R(i(k),j(k)) and A057043(n)=i(L(n)), where L(n) is the n-th Lucas number.at n=41A057043
- Number of integers k such that phi(k) = 10^n.at n=23A072074
- Position of first repeat of the opening sequence of length n occurring after the first repeat of the opening sequence of length n-1 in the Kolakoski sequence (A000002).at n=32A074300
- "Orderly" Friedman numbers (or "good" or "nice" Friedman numbers): Friedman numbers (A036057) where the construction digits are used in the proper order.at n=20A080035
- Number of 8 X 8 pandiagonal Franklin squares with magic sum 4n.at n=4A125116
- Friedman numbers n such that n+1 is also a Friedman number.at n=31A195420
- Number of zero-sum -1..1 arrays of n elements with first and second differences also in -1..1.at n=17A201866