9525
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 15872
- Proper Divisor Sum (Aliquot Sum)
- 6347
- 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
- 5040
- Möbius Function
- 0
- Radical
- 1905
- 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
- 78
- 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) = (d(n)-r(n))/2, where d = A026057 and r is the periodic sequence with fundamental period (0,0,1,0).at n=41A026058
- Numbers n such that n^2 can be obtained from n by inserting internal (but not necessarily contiguous) digits.at n=42A046851
- Smallest odd number k such that p(2m)-2p(m)=k has exactly n solutions (where p(m) = m-th prime).at n=10A069890
- Partial sums of A001764.at n=7A104859
- Difference between n-th prime squared and n-th perfect square.at n=25A106588
- Expansion of (eta(q)^3*eta(q^10)^6)/(eta(q^2)^2*eta(q^5)^7) in powers of q.at n=39A113977
- Total number of parts that appear exactly once in the partitions of n into odd parts.at n=52A116665
- Number of partitions of n into "number of partitions of n into 'number of partitions of n into partition numbers' numbers" numbers.at n=50A130899
- Nearest integer to the space diagonal of the smallest (measured by the longest edge) primitive (gcd(a,b,c)=1) Euler bricks (a, b, c, sqrt(a^2 + b^2), sqrt(b^2 + c^2), sqrt(a^2 + c^2) are integers). If the space diagonal is an integer then the Euler brick is called a "perfect cuboid". There are no known perfect cuboids.at n=16A141029
- Number of ways to partition an n X 4 grid into 4 connected equal-area regions.at n=6A167248
- T(n,m) = Number of ways to partition an nXm grid into 4 connected equal-area regions.at n=48A167260
- T(n,m) = Number of ways to partition an nXm grid into 4 connected equal-area regions.at n=51A167260
- Number of tilings of a 7 X n rectangle with n heptominoes of any shape.at n=4A174251
- Number of 4-bead necklaces labeled with numbers -n..n not allowing reversal, with sum zero and first and second differences in -n..n.at n=47A209008
- Triangle read by rows: row sums, right and left borders are the Bell sequence, or a shifted variant. See Comments for precise definition.at n=49A212431
- Numbers n such that sum of squares of digits of n equals the sum of prime divisors of n.at n=22A217390
- Expansion of A(x) satisfying A(A(x)) = x+2x^2+4x^3.at n=11A220110
- Prime sieve of e.at n=30A248804
- Expansion of Product_{k>=1} 1/(1 - (3*k-1)*x^(3*k-1)).at n=23A265820
- a(n) = r*a(ceiling(n/2))+s*a(floor(n/2)) with a(1)=1 and (r,s)=(4,1).at n=35A268527