7090
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 12780
- Proper Divisor Sum (Aliquot Sum)
- 5690
- 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
- 2832
- Möbius Function
- -1
- Radical
- 7090
- 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
- 57
- 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
- Numbers k such that the continued fraction for sqrt(k) has period 15.at n=34A020354
- Expansion of 1/((1-x)(1-7x)(1-9x)(1-10x)).at n=3A024441
- Multiplicity of highest weight (or singular) vectors associated with character chi_73 of Monster module.at n=42A034461
- Number of partitions of n with equal nonzero number of parts congruent to each of 3 and 4 (mod 5).at n=42A035571
- Number of partitions of n into parts not of form 4k+2, 24k, 24k+7 or 24k-7. Also number of partitions in which no odd part is repeated, with at most 3 parts of size less than or equal to 2 and where differences between parts at distance 5 are greater than 1 when the smallest part is odd and greater than 2 when the smallest part is even.at n=45A036032
- Numbers k such that 7^k - 2 is a prime.at n=24A090669
- Number of one-element transitions among partitions of the integer n for unlabeled parts.at n=20A093695
- Number of permutations of length n that avoid the patterns 132, 4321.at n=18A116701
- a(n)=7*a(n-1)-5*a(n-2), a(0)=1, a(1)=5.at n=5A147837
- 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, 1), (0, 1, -1), (0, 1, 1), (1, -1, 1)}.at n=8A148915
- 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, -1, 1), (0, 1, 1), (1, 1, 0)}.at n=7A150482
- Number of planar triangular n X n X n nonnegative integer grids with every similarly oriented 4 X 4 X 4 subtriangle summing to 4.at n=2A154042
- Number of 4-step S, NW and NE-moving king's tours on an n X n board summed over all starting positions.at n=17A187378
- Number of (n+3) X (n+3) 0..2 matrices with each 4 X 4 subblock idempotent.at n=5A224720
- Number of (n+3) X 9 0..2 matrices with each 4 X 4 subblock idempotent.at n=5A224726
- Numbers k such that 10^k + 103 is prime.at n=26A258932
- a(n) begins the first chain of 9 consecutive positive integers of h-values with symmetrical gaps about the center, where h(k) is the length of the finite sequence k, f(k), f(f(k)), ...., 1 in the Collatz (or 3x + 1) problem.at n=30A268288
- The diagonal of the rational function 1/(1 - x - y - x y - x z - y z).at n=4A268542
- Number of 2 X 2 matrices with all terms in {0,1,...,n} and (sum of terms) = determinant.at n=42A280588
- a(n) is the number of terminal states that can be achieved via the following algorithm: start with n piles each containing one stone; stones can be transferred between piles only when the piles start with the same number of stones.at n=55A292728