15306
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 30624
- Proper Divisor Sum (Aliquot Sum)
- 15318
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- yes
Derived Values
- Euler's Totient
- 5100
- Möbius Function
- -1
- Radical
- 15306
- 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
- yes
- Odd
- no
Appears in sequences
- a(n) = a(n-1) + a(n - 1 - number of even terms so far).at n=46A006336
- Numbers which are the sum of their proper divisors containing the digit 5.at n=24A059464
- Number of ways a loop can cross three roads meeting in a Y n times.at n=12A085919
- Numbers n such that n/6 and prime(n)+/-n are all primes.at n=25A105550
- Numbers k such that the k-th triangular number contains only digits {1,4,7}.at n=4A119127
- a(1)=1, a(2)=1. a(n) = the sum of the two largest earlier terms which are both coprime to n.at n=58A122457
- Triangle T(n,k): the coefficient of [x^k] of the series -(x-1)^(2*n+1) *Sum_{j>=0} (j+1)^n *binomial(j,n) * x^(j-n); columns 0<=k<n.at n=11A155163
- Expansion of 1/(1-x^2-x^3+x^7-x^8+x^10).at n=45A174577
- Triangle of coefficients of the numerator polynomials of the rational o.g.f.'s of the diagonals of A059297.at n=14A202017
- Numbers k with the property that p = k^2 - 13 and q = k^2 + 13 are consecutive primes.at n=35A248785
- Numbers n such that 4n + 1, 4n + 2 and 4n + 3 are not squarefree.at n=36A258332
- Number of (n+2)X(3+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000000 00000001 or 00001011.at n=5A260279
- Number of (n+2)X(6+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000000 00000001 or 00001011.at n=2A260282
- T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000000 00000001 or 00001011.at n=30A260284
- T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000000 00000001 or 00001011.at n=33A260284