7305
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 11712
- Proper Divisor Sum (Aliquot Sum)
- 4407
- 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
- 3888
- Möbius Function
- -1
- Radical
- 7305
- 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
- no
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 194
- 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
- no
- Odd
- yes
Appears in sequences
- E.g.f.: exp(arcsin(x)+log(x+1)).at n=8A012899
- Pisot sequence P(6,11), a(0)=6, a(1)=11, a(n+1) is the nearest integer to a(n)^2/a(n-1).at n=12A021011
- (1/4 - 1/6 + ... + d/c(n))*LCM{4, 6, ..., c(n)}, where d = (-1)^(n-1), c(n) = n-th composite number.at n=13A025546
- Number of days in n years (n=4 is the first leap year).at n=19A033171
- Number of days in n years (n=3 is the first leap year).at n=19A033172
- Number of days in n years (n=2 is the first leap year).at n=19A033173
- Number of days in n years (n=1 is the first leap year).at n=19A033174
- Number of nonempty subsets of {1,2,...,n} in which exactly 1/4 of the elements are <= (n-2)/3.at n=15A048019
- Number of nonempty subsets of {1,2,...,n} in which exactly 1/4 of the elements are <= (n-3)/3.at n=15A048030
- Number of nonempty subsets of {1,2,...,n} in which exactly 1/4 of the elements are <= sqrt(n).at n=15A048096
- Revert transform of 2*x*(1 - x + x^2 - x^3)-x/(1+x).at n=11A049173
- Number of unimodal partitions/compositions of n into distinct terms.at n=34A072706
- Number of distinct representations of 8n^3 as the sum of two primes.at n=47A116981
- Nonprime numbers k such that k divides 3^((k+1)/2) - 2^((k+1)/2) - 1.at n=7A130062
- Indices k such that A020507(k)=Phi[k](-8) is prime, where Phi is a cyclotomic polynomial.at n=25A138922
- 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, 0), (-1, 0, -1), (-1, 1, 1), (1, 0, 0)}.at n=10A148066
- Diagonal sums of number triangle A113582.at n=22A154324
- Numbers n which divide the periodic part (with zeros at end) of the decimal expansion of 1/n.at n=9A179267
- Number of nX6 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 1 0 0 vertically.at n=3A207498
- T(n,k)=Number of nXk 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 1 0 0 vertically.at n=39A207500