4742
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 7116
- Proper Divisor Sum (Aliquot Sum)
- 2374
- 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
- 2370
- Möbius Function
- 1
- Radical
- 4742
- 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
- 152
- 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
- Molien series for full 8 X 8 Siegel modular group H_3 of order 371589120.at n=35A027633
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 68.at n=7A031566
- Decimal part of cube root of a(n) starts with 8: first term of runs.at n=15A034134
- Expansion of Molien series for relative invariants of 8-dimensional complex Clifford group.at n=16A043330
- a(n) = a(1) + a(2) + ... + a(n-1) + a(m) for n >= 4, where m = 2^(p+1) + 2 - n 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) = 4.at n=12A049945
- a(1) = 4; a(n) = smallest composite number of the form k*a(n-1) + 1.at n=36A061766
- Rounded total surface area of a regular octahedron with edge length n.at n=37A071396
- Prime(a(n)) + ... + prime(a(n)+3) is a square = A051395(n)^2.at n=13A072849
- Interprimes (A024675) which are of the form s*prime, s=2.at n=33A075277
- a(n) = A077706(n+1)/A077706(n).at n=10A077707
- a(n) = {A089713(n)+A070219(n)}/2.at n=44A089715
- a(n) = Sum_{k=1..n} floor(binomial(n,k)/k).at n=15A101687
- a(1) = a(2) = 1; for n>2, a(n+1) = a(n) + a(n-1) iff a(n) is prime, otherwise a(n+1) = a(n) + 1.at n=49A113051
- Smallest semiprimes such that a(j) - a(k) are all different.at n=46A135257
- 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, 0), (0, 0, 1), (1, -1, -1), (1, 1, 0)}.at n=7A150165
- Triangle, read by rows, where T(n,k) = Sum_{i=k..n-1} T(n-1,i)*T(i+1,k+1) for n>k with T(n,n) = n+1 for n>=0.at n=24A152541
- Expansion of (1 + 4*x - x^2 - 2*x^3)/(1 - 3*x - 14*x^2 + 15*x^3 + 7*x^4).at n=5A177140
- Total number of even parts in the last section of the set of partitions of n.at n=30A206434
- Triangle of coefficients of polynomials u(n,x) jointly generated with A209768; see the Formula section.at n=40A209767
- Trajectory of 80 under the map n-> A006368(n).at n=34A223087