12545
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 16296
- Proper Divisor Sum (Aliquot Sum)
- 3751
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 9216
- Möbius Function
- -1
- Radical
- 12545
- 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
- 63
- 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
- Odd octagonal numbers: (2n+1)*(6n+1).at n=32A014641
- Pseudoprimes to base 14.at n=35A020142
- Least k such that first k terms of A022300 contain n more 2's than 1's.at n=16A025515
- Number of nonempty subsets of {1,2,...,n} in which exactly 1/4 of the elements are <= n/3.at n=16A047196
- Number of nonempty subsets of {1,2,...,n} in which exactly 1/4 of the elements are <= (n-1)/3.at n=16A048008
- Number of nonempty subsets of {1,2,...,n} in which exactly 1/4 of the elements are <= (n-2)/3.at n=16A048019
- Numbers n such that phi(n-1) + phi(n+1) = phi(2n).at n=11A067701
- Composite n such that (n-1)*phi(n) is a perfect square.at n=20A069953
- a(n) = ( A077059(n)^2 + A077060(n)^2 )^(1/3).at n=33A077061
- Indices of primes in sequence defined by A(0) = 13, A(n) = 10*A(n-1) + 33 for n > 0.at n=11A102023
- Smaller sides (a) in (a,a,a+1)-integer triangle with integer area.at n=4A103974
- a(n) = 16*n^2 + 1.at n=27A108211
- a(n) = 3*a(n-1) + 3*a(n-2) - a(n-3); a(0)=1, a(1)=1, a(2)=5.at n=8A120893
- Composite number of the form 4n^2+1.at n=36A121944
- 3-almost prime octagonal numbers.at n=13A129927
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (-1, 0, 1), (0, 0, 1), (0, 1, -1), (1, -1, 1)}.at n=10A148157
- a(n) = (n-2)^4 - a(n-1) - a(n-2), with a(1) = a(2) = 0.at n=14A152729
- Numbers n with property that A077116(n) is nonzero square.at n=44A154101
- a(n) = 81*n^2 - 90*n + 26.at n=13A154295
- a(n) = 392*n + 1.at n=32A158002