7556
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
- 6
- Divisor Sum
- 13230
- Proper Divisor Sum (Aliquot Sum)
- 5674
- 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
- 3776
- Möbius Function
- 0
- Radical
- 3778
- Omega Function (Ω)
- 3
- 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
- 83
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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 6-level labeled rooted trees with n leaves.at n=5A000405
- Number of n-step self-avoiding walks on hexagonal lattice from (0,0) to (0,3).at n=6A005549
- Number of n-step mappings with 5 inputs.at n=5A005946
- Numbers k such that the continued fraction for sqrt(k) has period 66.at n=36A020405
- Decimal part of n-th root of a(n) starts with digit 6.at n=17A034083
- Base-7 palindromes that start with 3.at n=23A043017
- Number of n X 3 binary arrays with a path of adjacent 1's from upper left corner to anywhere in right hand column.at n=3A069294
- Number of 5 X n binary arrays with a path of adjacent 1's from upper left corner to anywhere in right hand column.at n=1A069309
- Numbers n such that (sigma(n-2)+sigma(n+2))/2 = sigma(n).at n=25A099631
- First differences of indices of A000043.at n=31A135701
- Square array A(n,k), n >= 0, k >= 0, read by antidiagonals, where the e.g.f. of column k is 1+g^(k+1)(x) with g = x-> exp(x)-1.at n=60A144150
- Array read by antidiagonals of higher order Bell numbers.at n=40A153277
- Least of 4 consecutive integers such that their product +-5 are primes.at n=41A174244
- a(n) = Sum_{i+j=n, i,j >= 1} tau(i)*sigma(j), where tau() = A000005(), sigma() = A000203().at n=52A191831
- Total number of parts greater than 1 in all partitions of n minus the number of partitions of n into parts each less than n.at n=25A198381
- Number of partitions p of n such that the number of parts having multiplicity 1 is a part and max(p) - min(p) is a part.at n=43A241447
- Composite numbers n such that the quadratic form x^2+n*y^2 does not represent a prime strictly between n and 2n.at n=60A244030
- Numbers k such that k, k+1, k+2, and k+3 are not divisible by any of their nonzero digits.at n=32A244358
- Number of ways to start with set {1,2,...,n} and then repeat n times: partition each set into subsets.at n=5A261280
- a(1) = 10, a(n) = smallest number > a(n-1) such that the concatenation of a(n-1) and a(n) is a square.at n=6A265150