1615
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 13
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 2160
- Proper Divisor Sum (Aliquot Sum)
- 545
- 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
- 1152
- Möbius Function
- -1
- Radical
- 1615
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 73
- 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
- Number of n-node rooted trees of height 7.at n=12A000418
- Degrees of irreducible representations of Janko group J3.at n=12A003906
- Coordination sequence T2 for Zeolite Code EMT.at n=33A008087
- Coordination sequence T4 for Zeolite Code LTN.at n=28A008143
- Coordination sequence T2 for Zeolite Code YUG.at n=26A008248
- Expansion of Product (1 - x^k)^10 in powers of x.at n=24A010818
- Expansion of Product_{k>=1} (1 - x^k)^20.at n=4A010826
- Expansion of Product_{k>=1} (1 - x^k)^20.at n=8A010826
- Numbers k such that phi(k + 11) | sigma(k).at n=38A015831
- Numbers k such that phi(k + 13) | sigma(k).at n=48A015833
- Pseudoprimes to base 69.at n=13A020197
- Pseudoprimes to base 84.at n=7A020212
- Strong pseudoprimes to base 84.at n=1A020310
- Ordered areas (divided by 6) of primitive Pythagorean triangles (with multiple entries).at n=45A020885
- a(n) = n*(9*n - 1)/2.at n=19A022266
- a(n) = F(n+3) + c(n) where F(k) is k-th Fibonacci number and c(n) is n-th number that is 1 or 2 or is not a Fibonacci number.at n=13A022809
- Numbers k such that Fibonacci(k) == 5 (mod k).at n=48A023176
- a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n+1-k), where k = [ (n+1)/2 ], s = A023532, t = A001950 (upper Wythoff sequence).at n=45A024374
- Number of 6's in all partitions of n.at n=28A024790
- a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = A023532, t = A001950 (upper Wythoff sequence).at n=44A025074