7574
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 23
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 13008
- Proper Divisor Sum (Aliquot Sum)
- 5434
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 3240
- Möbius Function
- -1
- Radical
- 7574
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 83
- 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
- Number of trivalent connected simple graphs with 2n nodes and girth at least 6.at n=12A014374
- Fibonacci sequence beginning 5, 17.at n=14A022141
- s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n+1-k), where k = [ (n+1)/2 ], s = A023532, t = (Fibonacci numbers).at n=18A024367
- a(n) = Sum_{k=1..n} (n-k) * floor(n/k).at n=47A024920
- a(n) = n^2 + (n+1)^2 + (n+2)^2 + (n+3)^2.at n=42A027575
- Expansion of 1/((1-3x)(1-6x)(1-8x)(1-11x)).at n=3A028081
- Number of partitions of n with equal number of parts congruent to each of 1 and 2 (mod 3).at n=39A035536
- Number of partitions of 3n with same number of parts == 1 (mod 3) and == 2 (mod 3).at n=13A035592
- Used by Polya in calculating A000598.at n=15A036676
- Numbers whose base-5 representation contains exactly three 2's and two 4's.at n=32A045291
- a(n) = a(n-1) + a(m) for n >= 4, where m = 2*n - 3 - 2^(p+1) and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = a(2) = 1 and a(3) = 2.at n=45A050028
- a(n) = a(n-1) + a(m) for n >= 4, where m = 2*n - 3 - 2^(p+1) and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = 1 and a(2) = a(3) = 2.at n=45A050044
- a(n) = a(n-1) + a(m) for n >= 4, where m = 2*n - 3 - 2^(p+1) and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = 1, a(2) = 3, and a(3) = 2.at n=45A050060
- Numbers k such that 201*2^k-1 is prime.at n=35A050852
- Expansion of e.g.f. log(-1/(-2+exp(x)))*x.at n=7A052862
- Numbers that are sums of 2 or more consecutive squares in more than 1 way.at n=14A062681
- Largest term in periodic part of continued fraction expansion of square root of 1+3^n or 0 if 1+3^n is square.at n=14A077626
- Largest term in periodic part of continued fraction expansion of square root of -1+3^n.at n=14A077627
- Numbers k such that the product of Euler phi of the 2 consecutive integers {k,k+1} is a 4th power: if sqrt(sqrt(phi(k)*phi(k+1))) is an integer, then k is here.at n=5A082788
- Triangle T, read by rows, that satisfies: T(n,k) = [T^2](n-1,k) for n>k+1>=1, with T(n,n) = 1 and T(n+1,n) = n+1 for n>=0, where T^2 is the matrix square of T.at n=37A109152