12542
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 18816
- Proper Divisor Sum (Aliquot Sum)
- 6274
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6270
- Möbius Function
- 1
- Radical
- 12542
- 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
- 112
- 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
- yes
- Odd
- no
Appears in sequences
- a(n)-th and (a(n)+1)-st primes are the first pair of primes that differ by exactly 2n; a(n) = -1 if no such pair of primes exists.at n=33A038664
- G.f. = continued fraction: A(x)=1/(1-x-x^2-x^3/(1-x^4-x^5-x^6/(1-x^7-x^8-x^9/(...)))).at n=16A088353
- EULER transform of A001511.at n=23A092119
- Smoothed lengths of the B blocks in analysis of A090822.at n=12A095828
- a(n) = 3*Fibonacci(n) + (-1)^n.at n=19A097133
- Numbers k such that 10^k*(10^7*(-1+10^k)+6083806) + 10^k - 1 is prime.at n=10A107291
- Triangle T, read by rows, where T(n,k) = [T^2](n-1,k) + [T^2](n-2,k-1) (n>k>0), with T(n,0) = [T^2](n-1,0) (n>0) and T(n,n) = 1 (n>=0), where T^2 is the matrix square of T.at n=36A109316
- Triangle T, read by rows, where T(n,k) = [T^2](n-1,k) + [T^2](n-2,k-1) (n>k>0), with T(n,0) = [T^2](n-1,0) (n>0) and T(n,n) = 1 (n>=0), where T^2 is the matrix square of T.at n=37A109316
- Column 0 of triangle T=A109316 where T(n,k) = [T^2](n-1,k) + [T^2](n-2,k-1) and T^2 is the matrix square of T.at n=8A109317
- Triangle, read by rows, equal to the matrix 4th power of triangle A136220.at n=16A136232
- Matrix square of triangle U = A136228, read by rows.at n=16A136233
- 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, 0, 1), (0, 1, 0), (1, -1, 1), (1, 1, -1)}.at n=9A148410
- Least number x such that there are n numbers of the form 6k-1 or 6k+1 between prime(x) and prime(x+1).at n=22A213903
- Number of nX3 arrays of occupancy after each element moves to some king-move neighbor.at n=2A221190
- T(n,k)=Number of nXk arrays of occupancy after each element moves to some king-move neighbor.at n=12A221192
- Let v = list of denominators of Farey series of order n (see A006843); a(n) = sum of products of adjacent terms of v.at n=16A278046
- a(n)=position of the first occurrence of a local maximum equal to 2n in A001223, n>1.at n=32A286729
- Möbius transform of A341512, sigma(n)*A003961(n) - n*sigma(A003961(n)).at n=47A346239
- Number of tilings of a 5 X n rectangle using n pentominoes of shapes T, N, X.at n=43A361250
- a(n) = a(n-1) + a(n-2) + 1 with a(0)=2 and a(1)=2.at n=18A377628