1532
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 11
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 2688
- Proper Divisor Sum (Aliquot Sum)
- 1156
- 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
- 764
- Möbius Function
- 0
- Radical
- 766
- Omega Function (Ω)
- 3
- Little Omega Function (ω)
- 2
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
- 47
- 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
- yes
- Odd
- no
Appears in sequences
- Number of series-parallel networks with n unlabeled edges. Also called yoke-chains by Cayley and MacMahon.at n=8A000084
- Conjecturally largest even integer which is an unordered sum of two primes in exactly n ways.at n=22A000954
- a(n) = ceiling(1000*log_10(n)).at n=33A004227
- Coordination sequence T6 for Zeolite Code BOG.at n=28A008054
- Coordination sequence T2 for Moganite, also for BGB1.at n=25A008259
- If a, b in sequence, so is ab+4.at n=31A009303
- Expansion of e.g.f.: tan(log(1+tanh(x))).at n=7A009640
- Coordination sequence for MgNi2, Position Ni2.at n=10A009932
- Numbers k such that phi(k) + 10 | sigma(k + 10).at n=38A015789
- a(n) = a(n-3) + a(n-4), with a(0)=1, a(1)=a(2)=0, a(3)=1.at n=43A017817
- Numbers k such that Fibonacci(k) == -3 (mod k).at n=24A023164
- a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n+1-k), where k = [ (n+1)/2 ], s = (1, p(1), p(2), ...), t = (F(2), F(3), ...).at n=11A024481
- a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (1, p(1), p(2), ...), t = (F(2), F(3), F(4), ...).at n=10A025101
- Least k such that first k terms of A006928 contain n more 1's than 2's.at n=12A025506
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 18.at n=33A031516
- Numbers k such that 21*2^k+1 is prime.at n=18A032360
- Numbers k such that 165*2^k+1 is prime.at n=34A032459
- Base-2 digital convolution sequence.at n=33A033639
- a(n) = floor(E_(n+1)/E_(n)) where E_n is n-th Euler number (see A028296 and A000364).at n=29A034971
- First differences give (essentially) A028242.at n=22A035107