12755
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 15312
- Proper Divisor Sum (Aliquot Sum)
- 2557
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 10200
- Möbius Function
- 1
- Radical
- 12755
- 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
- 81
- 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(n) = floor(2nd elementary symmetric function of Sum_{j=1..k} 1/j, k = 1,2,...,n).at n=44A025212
- [ exp(13/14)*n! ].at n=6A030916
- Numbers k such that 189*2^k-1 is prime.at n=34A050846
- Numbers k such that 7*10^k - 9 is prime.at n=22A103048
- Divide primes in groups with 2n+1 elements and add together.at n=10A109725
- a(n) = a(n-1) + a(floor(n/2)) + a(ceiling(n/2)).at n=31A131205
- Numbers n such that n!8-2 is prime.at n=50A204664
- Number of (w,x,y,z) with all terms in {1,...,n} and w*x+y*z<n^2.at n=11A212111
- Number of (n+2)X(7+2) 0..1 arrays with every 3X3 subblock sum of the two sums of the diagonal and antidiagonal minus the two minimums of the central column and central row nondecreasing horizontally, vertically and ne-to-sw antidiagonally.at n=22A254906
- Total area of all squares with squarefree side length |s - t|, such that n = s + t, and s < t, where s and t are positive integers.at n=44A303052
- Total area of all squares with squarefree side length |s - t|, such that n = s + t, and s < t, where s and t are positive integers.at n=46A303052