12745
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 15300
- Proper Divisor Sum (Aliquot Sum)
- 2555
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 10192
- Möbius Function
- 1
- Radical
- 12745
- 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
- Numerators of continued fraction convergents to sqrt(771).at n=8A042486
- Sizes of successive balls in D_4 lattice.at n=35A046949
- a(n) = 10*n^2 - 6*n + 1.at n=35A087348
- Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1000-1001-1111 pattern in any orientation.at n=14A147137
- 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, -1, 0), (-1, 0, 0), (1, 0, -1), (1, 1, 1)}.at n=8A149543
- Number of n X 2 0..3 arrays with rows and columns lexicographically nondecreasing read forwards and nonincreasing read backwards.at n=31A201975
- Concatenation of n-th prime and n-th nonprime.at n=30A253910
- G.f.: 1/((1-t^11)^2*(1-t)*(1-t^3)*(1-t^5)*(1-t^7)*(1-t^9)*(1-t^13)*(1-t^15)*(1-t^17)*(1-t^19)*(1-t^21)).at n=61A266751
- Record values of A018799 (Smallest nonnegative integer m such that m! begins with n in base 10).at n=24A279089
- Square array A(n,k), n>=0, k>=0, read by antidiagonals, where column k is the expansion of Product_{j>=1} 1/(1 - j*x^j)^(j^k).at n=50A294589
- Main diagonal of A332357.at n=16A332358
- Number of vertices formed when n equally spaced points are placed around a circle and all pairs of points are joined by an interior arc whose radius equals the circle's radius.at n=23A371254