12319
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 12544
- Proper Divisor Sum (Aliquot Sum)
- 225
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 12096
- Möbius Function
- 1
- Radical
- 12319
- Omega Function (Ω)
- 2
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 94
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- 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
- a(1) = 1, a(n) = 2*a(n-1) + a([n/2]).at n=12A033489
- Composite numbers n such that the sum of divisors of n, sigma(n), divided by the number of divisors, d(n) and sigma(n) minus n are both rational squares.at n=6A049226
- a(n) = 4*n^4 + 8*n^3 - 4*n - 1 = (2*n^2 - 1)*(2*n^2 + 4*n + 1).at n=7A057769
- Smallest solution m to (n+1)*phi(m) = n*sigma(m), or -1 if no solution exists.at n=26A065824
- a(n) = A065824(A047845(n+1)).at n=11A065884
- Number of ones in the binary expansion of A068943(n).at n=10A068945
- Trajectory of n under the Reverse and Add! operation carried out in base 4 (presumably) does not reach a palindrome and (presumably) does not join the trajectory of any term m < n.at n=34A075421
- Numbers k such that 7*(10^k - 1)/9 + 10^floor(k/2) is a palindromic wing prime (a.k.a. near-repdigit palindromic prime).at n=7A077793
- Difference between squares of legs of primitive Pythagorean triangles, sorted (with multiplicity).at n=30A127923
- Numbers which are the sum of 3 cubes of distinct odd primes.at n=33A138853
- Numbers n with property that n^2 is a concatenation of three 3-digit primes.at n=8A153139
- a(n) = n^3 + 73*n^2 + n + 67.at n=12A163303
- Members of A167490 sorted in ascending order.at n=46A167491
- Values of 16*n^2+24*n+7, n>=0, each duplicated.at n=54A173294
- Values of 16*n^2+24*n+7, n>=0, each duplicated.at n=55A173294
- Numbers n such that sum of divisors, sigma(n), and sum of the proper divisors, sigma(n)-n, are both square.at n=8A176996
- Number of (n+1) X 2 0..3 arrays with every 2 X 2 subblock having nonzero determinant and commuting with every horizontal or vertical neighbor.at n=8A206336
- T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with every 2X2 subblock having nonzero determinant and commuting with every horizontal or vertical neighbor.at n=36A206343
- T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with every 2X2 subblock having nonzero determinant and commuting with every horizontal or vertical neighbor.at n=44A206343
- Nonprime terms in A210494.at n=13A230214