7605
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 18
- Divisor Sum
- 14274
- Proper Divisor Sum (Aliquot Sum)
- 6669
- 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
- 3744
- Möbius Function
- 0
- Radical
- 195
- Omega Function (Ω)
- 5
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 31
- 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
- no
- Odd
- yes
Appears in sequences
- a(n) = 5*n^2.at n=39A033429
- Base-7 palindromes that start with 3.at n=24A043017
- Numbers k such that k | sigma_13(k) - phi(k)^13.at n=17A055707
- Numbers k that can be expressed as k = w+x = y*z with w*x = (y+z)^2 where w, x, y, and z are all positive integers.at n=17A057369
- For the numbers k that can be expressed as k = w + x = y*z with w*x = y^2 + z^2 where w, x, y, and z are all positive integers, this sequence gives the corresponding values of w*x.at n=6A057444
- n is odd and sum of digits of n equals the numbers of divisors of n.at n=35A057532
- 2-apexes of omega: numbers k such that omega(k-2) < omega(k-1) < omega(k) > omega(k+1) > omega(k+2), where omega(m) = the number of distinct prime factors of m.at n=41A076762
- 2-nadirs of phi: numbers k such that phi(k-2) > phi(k-1) > phi(k) < phi(k+1) < phi(k+2).at n=39A076773
- n is divisible by the sum of all divisors of n which are less than the square root of n (values of n where 1 is the only divisor less than sqrt(n) are excluded as trivial cases.).at n=36A088345
- Values of r such that N(r)/r^2 > Pi, where N(r) is the number of integer lattice points (x,y) inside or on a circle of radius r.at n=41A093832
- Odd interprimes divisible by 13.at n=33A124619
- Numbers k for which nontrivial positive magic squares of exactly 8 different orders with magic sum k exist. For a definition of nontrivial positive magic squares, see A125005.at n=37A125015
- Expansion of 1/(1 - x - 3x^2 + x^3).at n=12A125691
- 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), (1, 0, 0), (1, 0, 1)}.at n=8A149889
- Partial sums of round(n^2/5).at n=48A173690
- Triangle read by rows:s(n,m)=Sum[StirlingS2[n, k]*StirlingS1[n - k, m]* Binomial[n, k]*(-1)^(m - k), {k, 0, n}];t[n,m]=s[n,m]+s[n,n-m].at n=26A174555
- Triangle read by rows:s(n,m)=Sum[StirlingS2[n, k]*StirlingS1[n - k, m]* Binomial[n, k]*(-1)^(m - k), {k, 0, n}];t[n,m]=s[n,m]+s[n,n-m].at n=22A174555
- a(n) is the number of non-isomorphic geometric realizations (rectilinear drawings) of K_{2,n}.at n=7A180487
- T(n,m)=Number of (n+1)X3 0..m arrays with every 2X2 subblock commuting with each of its horizontal and vertical 2X2 subblock neighbors.at n=37A190023
- Number of parts that are visible in one of the three views of the shell model of partitions version "Tree" with n shells.at n=28A194803