12142
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 10
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 19656
- Proper Divisor Sum (Aliquot Sum)
- 7514
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5592
- Möbius Function
- -1
- Radical
- 12142
- 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
- 156
- 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
- yes
- Odd
- no
Appears in sequences
- Expansion of 1 / ((1-x)^2*(1-x^2)*(1-x^3)*(1-x^4)).at n=46A002621
- Write the numbers from 1 to n^2 in a spiraling square; a(n) is the total of the sums of the two diagonals.at n=21A059924
- Number of homogeneous generators of degree n for graded algebra associated with meanders.at n=9A060149
- Numbers n such that 2*10^n + 4*R_n + 5 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=9A102955
- Row sums of triangle A134464.at n=38A134465
- Numbers k such that (sum of base-2 digits of k) = (sum of base-10 digits of k) = 10.at n=18A152207
- a(n+1)-+a(n)=prime, a(n+1)*a(n)=Average of twin prime pairs, a(1)=2,a(2)=9.at n=38A154495
- Number of nonempty subsets of {1, 2, ..., n} with <= 4 pairwise coprime elements.at n=36A187265
- Number of 2 X 2 matrices M of positive integers such that permanent(M) < n.at n=46A212151
- Number of n X 2 arrays of the minimum value of corresponding elements and their horizontal or vertical neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 n X 2 array.at n=19A219589
- Number of (n+1)X(1+1) 0..1 arrays x(i,j) with row sums sum{j*x(i,j), j=1..1+1} nondecreasing, and column sums sum{i*x(i,j), i=1..n+1} nondecreasing.at n=45A232825
- Number of enriched p-trees of weight n with distinct leaves.at n=23A300354
- The number of random walks on the simple square lattice that return to the origin (0,0) after 2n steps and do not pass through (0,0) or (1,0) at intermediate steps.at n=4A337869
- Number of permutations of [n] where each pair of adjacent elements is coprime and does not differ by a prime.at n=24A368958