15480
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 48
- Divisor Sum
- 51480
- Proper Divisor Sum (Aliquot Sum)
- 36000
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4032
- Möbius Function
- 0
- Radical
- 1290
- Omega Function (Ω)
- 7
- 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
- 146
- 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
- E.g.f. (1-x)^3/(1-4x+3x^2-x^3).at n=5A052603
- Number of 5-ary sequences with primitive period n.at n=6A054720
- Number of step cyclic shifted sequences using exactly five different symbols.at n=8A056418
- Number of primitive (period n) step cyclic shifted sequences using exactly five different symbols.at n=8A056427
- Number of primitive (aperiodic) palindromes using a maximum of five different symbols.at n=11A056461
- Numbers k such that sigma(x) = k has exactly 10 solutions.at n=25A060666
- First differences of A069475, successive differences of (n+1)^6-n^6.at n=19A069476
- a(n) = n^3 + 6*n^2 + 6*n + 1.at n=23A090197
- Numbers k such that the digits of sigma(k) are a permutation of those of k, in base 10.at n=20A115920
- a(n) = 2*n*(6*n-1).at n=36A126964
- a(0)=360, a(n)=a(n-1)+720 for n>=1.at n=21A140801
- Smallest multiple of n with a number of divisors >= n.at n=42A140965
- Table T(n,k) by antidiagonals. T(n,k) is the number of length n primitive (=aperiodic or period n) k-ary words (n,k >= 1).at n=50A143324
- Lower triangular array called S2hat(-2) related to partition number array A144274.at n=39A144275
- Coefficients of polynomial P(n) by rows, with P(n) = (x+1)^n + 2^(n-3)*((x+1)^n - x^n - 1) for n > 0 and P(0) = 1.at n=58A146769
- Number of 2 X 2 matrices having all elements in {-n,...n} and determinant 5.at n=36A209990
- Number of (w,x,y) with all terms in {0,...,n} and the numbers w,x,y,|w-x|,|x-y|,|y-w| distinct.at n=28A213493
- Number of length 6 primitive (=aperiodic or period 6) n-ary words.at n=5A218130
- a(n) = Sum_{i=0..n} digsum(i)^3, where digsum(i) = A007953(i).at n=39A231688
- Let m_n denote the number which is obtained from n-base representation of m if its digits are written in nondecreasing order; then a(n) is the smallest period of the sequence which is defined by the recurrence b(0)=0, b(1)=1, b(k)=(b(k-1) + b(k-2))_n, for k>=2, or a(n)=0, if there is no such period.at n=29A237671