2975
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
- 12
- Divisor Sum
- 4464
- Proper Divisor Sum (Aliquot Sum)
- 1489
- 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
- 1920
- Möbius Function
- 0
- Radical
- 595
- Omega Function (Ω)
- 4
- 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
- 48
- 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) = 3*n^2 + 3*n - 1.at n=31A004538
- Number of 5-dimensional centered tetrahedral numbers.at n=8A008499
- E.g.f.: exp(arcsinh(x)+tan(x)) = 1 + 2*x + 4/2!*x^2 + 9/3!*x^3 + 24/4!*x^4 + 97/5!*x^5 + ....at n=7A013091
- Numbers n such that phi(n + 9) | sigma(n) for n not congruent to 0 (mod 3).at n=47A015849
- Expansion of 1/((1-2x)*(1-8x)*(1-9x)).at n=3A016316
- Base 6 expansion uses each positive digit just once.at n=26A023744
- 5 times triangular numbers: a(n) = 5*n*(n+1)/2.at n=34A028895
- First differences of A037260.at n=20A037261
- Numbers k such that the string 6,5 occurs in the base 9 representation of k but not of k-1.at n=40A044310
- Numbers n such that string 7,5 occurs in the base 10 representation of n but not of n-1.at n=32A044407
- Numbers n such that string 7,5 occurs in the base 10 representation of n but not of n+1.at n=32A044788
- Number of nonempty subsets of {1,2,...,n} in which exactly 2/3 of the elements are <= (n-3)/3.at n=22A048029
- Coordination sequence T7 for Zeolite Code SFE.at n=36A057323
- Number of staircase polygons of area n with 2 (staircase polygon) holes on square lattice (not allowing rotations).at n=5A057415
- Numbers m such that m = 2*sigma(m)/3 - 1.at n=3A063906
- Numbers k such that (k!)^2 + prime(k) is prime.at n=9A064769
- Nonprimes m such that phi(m)*sigma(m) is divisible by m+1.at n=28A065148
- Nonprimes in A066720.at n=47A066721
- Composite numbers k with no prime factor among (2, 3) (cf. A038509) and such that phi(k) < 2*k/3.at n=10A069043
- Sum of the aliquot divisors of n-th Fibonacci number.at n=30A074283