7175
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 10416
- Proper Divisor Sum (Aliquot Sum)
- 3241
- 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
- 4800
- Möbius Function
- 0
- Radical
- 1435
- 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
- 75
- 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
- Centered octahedral numbers (crystal ball sequence for cubic lattice).at n=17A001845
- a(n) = C(n,1) + C(n,2) + C(n,3), or n*(n^2 + 5)/6.at n=35A004006
- a(n) = n*(23*n - 1)/2.at n=25A022280
- Least k such that the first k terms of A006928 contain n more 2's than 1's.at n=6A025507
- Number of partitions of n in which the least part is odd.at n=31A026804
- a(n) = (2*n+1)*(12*n+1).at n=17A033576
- Multiplicity of highest weight (or singular) vectors associated with character chi_127 of Monster module.at n=39A034515
- Number of ways of covering a 2n X 2n lattice by 2n^2 dominoes with exactly 4 horizontal (or vertical) dominoes.at n=3A038758
- Number of nonempty subsets of {1,2,...,n} in which exactly 2/3 of the elements are <= n/3.at n=21A047195
- Number of nonempty subsets of {1,2,...,n} in which exactly 2/3 of the elements are <= (n-1)/3.at n=21A048007
- Number of nonempty subsets of {1,2,...,n} in which exactly 2/3 of the elements are <= (n+1)/3.at n=21A048040
- 14-gonal (or tetradecagonal) numbers: a(n) = n*(6*n-5).at n=35A051866
- Number of 3 X 3 matrices, with elements from {0,...,n}, having the property that the middle element of each of the eight 3-element horizontal, vertical and diagonal lines equals the average of the two end elements.at n=34A059329
- a(n) = (2*n - 1)*(11*n^2 - 11*n + 6)/6.at n=12A063492
- Number of states in minimal automaton that recognizes biquanimous numbers in base n.at n=12A065023
- Taylor coefficients at x=0 of exp(exp(x^3/3+x^2/2)-1).at n=8A081096
- (p*q - 1)/2 where p and q are consecutive odd primes.at n=28A102770
- Array read by antidiagonals, generated by the matrix M = [1,1,1;1,N,1;1,1,1].at n=60A103280
- Records in A109734.at n=12A109739
- Integers i such that 41*i = 105 X i.at n=13A115876