12447
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
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 18480
- Proper Divisor Sum (Aliquot Sum)
- 6033
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 8280
- Möbius Function
- 0
- Radical
- 1383
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 2
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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 187
- 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
- no
- Odd
- yes
Appears in sequences
- Expansion of Product_{m>=1} (1 + m*q^m).at n=20A022629
- Discriminants of quintic fields with 2 complex conjugates (negated).at n=15A023684
- Number of partitions of n that do not contain 9 as a part.at n=35A027343
- Number of strings of n distinct digits from 0-9 that are the last n digits of a square in base 10.at n=5A036755
- a(n) = (-1)^(n+1) * Sum_{k=0..n} 16^k * B(2k) * C(2n+1,2k) where B(k) is the k-th Bernoulli number.at n=3A078794
- a(1)=0, and a(n+1) is the position of first occurrence of a(n) in the decimal expansion of 1/Pi.at n=21A098319
- a(n) = n*(4*n^2+5*n-3)/2.at n=17A126335
- Number of cusps in a class of degree-3n complex algebraic surfaces.at n=12A225018
- Numbers whose arithmetic derivatives are a permutation of their digits.at n=22A225902
- Number of partitions of n where the difference between consecutive parts is at most 6.at n=36A238866
- Integers of the form 8k+7 that can be written as a sum of four distinct squares of the form m, m+2, m+4, m+5, where m == 1 (mod 4).at n=13A243579
- Total number of torsion-free congruence subgroups of PSL(2,Z) of genus n.at n=13A258696
- Number of compositions of n into distinct parts where each part i is marked with a word of length i over a binary alphabet whose letters appear in alphabetical order.at n=12A261840
- Expansion of ((Product_{n>=1} (1 - x^(5*n))/(1 - x^n)^5) - 1)/5 in powers of x.at n=11A277974
- p-INVERT of (1,0,1,0,0,0,0,...), where p(S) = 1 - S^3.at n=28A291723
- Number of distinct pairs (m, y), where m >= 1 and y is an integer partition of n, such that m can be obtained by iteratively adding or multiplying together parts of y until only one part (equal to m) remains.at n=14A319910
- Number of partitions of n into 8 distinct and relatively prime parts.at n=42A340719
- a(n) is the least number k such that the sum of n^2 consecutive primes starting at prime(k) is a square.at n=31A357813
- Expansion of Sum_{k>0} (1/(1-x^k)^6 - 1).at n=13A363696
- Indices where prime(n) first appears in A373902.at n=29A371618