15655
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 19584
- Proper Divisor Sum (Aliquot Sum)
- 3929
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 12000
- Möbius Function
- -1
- Radical
- 15655
- 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
- 53
- 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
- Sums of 3 distinct powers of 5.at n=22A038475
- Obtainable by applying +, * and exponentiation to its own digits.at n=24A046469
- Squarefree n such that the elliptic curve n*y^2 = x^3 - x arising in the "congruent number" problem has rank 3.at n=25A062693
- "Orderly" Friedman numbers (or "good" or "nice" Friedman numbers): Friedman numbers (A036057) where the construction digits are used in the proper order.at n=34A080035
- Expansion of (1-2x)^2/((1-3x)(1-4x)).at n=7A093834
- Generalized Catalan triangle of Riordan type, called C(1,3).at n=40A116866
- Number of ways to build a contiguous building with n LEGO blocks of size 1 X 2 on top of a fixed block of the same size so that the building is flat, i.e., with all blocks in parallel position and symmetric after a rotation by 180 degrees.at n=14A123769
- a(n) = n^6 + 6n.at n=5A180356
- Monotonic ordering of nonnegative differences 2^i-9^j, for 40>=i>=0, j>=0.at n=37A192122
- Monotonic ordering of nonnegative differences 4^i-3^j, for 40>=i>=0, j>=0.at n=33A192148
- Monotonic ordering of nonnegative differences 4^i-9^j, for 40>= i>=0, j>=0.at n=19A192169
- a(n) = 5^n + 5*n.at n=6A221907
- Number of partitions of 2n such that (sum of parts having multiplicity 1) = sum of all other parts.at n=28A240447
- First row of A262057.at n=44A265316
- Number of n X 2 0..2 arrays with no element equal to any value at offset (-2,-1) (-2,1) or (-1,0) and new values introduced in order 0..2.at n=10A275222
- a(n) is the smallest K such that the power partition function P_n(k) is log-concave for all k > K.at n=3A346160
- Expansion of g.f. A(x) satisfying A(x)^5 = A( x^5/(1 - 5*x)^5 ).at n=6A361765
- Square array A(n,k), n>=0, k>=0, read by antidiagonals downwards, where column k is the expansion of (1 + x/(1-x)^k)^k.at n=72A381425
- Numbers that can be represented using their digits in the order of appearance, the operations +, -, *, /, ^, and any parentheses.at n=31A386936