15132
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 12
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 38416
- Proper Divisor Sum (Aliquot Sum)
- 23284
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4608
- Möbius Function
- 0
- Radical
- 7566
- Omega Function (Ω)
- 5
- Little Omega Function (ω)
- 4
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
- 133
- 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
- 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 82.at n=25A031580
- Numbers k such that the least term in the periodic part of the continued fraction for sqrt(k) is 82.at n=2A031760
- Triangle read by rows: T(n,k) is the number of Motzkin paths of length n having k returns (i.e., down steps hitting the x-axis).at n=51A097612
- a(n) = (2*n^3 + 5*n^2 - 11*n)/2.at n=23A162257
- Numbers that are repdigits with length > 2 in more than one base.at n=33A167783
- a(n) = smallest k such that sigma(k) = 14^n, or zero if no such k exists.at n=4A180265
- Triangle read by rows: T(n,k) is the number of peakless Motzkin paths of length n and having k UHD's starting at level 0; here U=(1,1), H=(1,0), and D=(1,-1).at n=52A190170
- Auxiliary r(n) sequence used to prove some properties about Rowland's sequence: r(1) = 1, and r(n) = 1/2*(c(n)+1), where c(n) is A190894, for n>1.at n=34A190895
- Monotonic ordering of set S generated by these rules: if x and y are in S then x^2+y^2-xy is in S, and 2 is in S.at n=18A192533
- a(n) = ceiling((n+1/n)^4).at n=10A197903
- Number of n X 2 binary arrays whose sum with another n X 2 binary array containing no more than a single 1 has rows and columns in lexicographically nondecreasing order.at n=16A225894
- Number of active (ON, black) cells at stage 2^n-1 of the two-dimensional cellular automaton defined by "Rule 347", based on the 5-celled von Neumann neighborhood.at n=6A271298
- Numbers k such that (73*10^k + 107)/9 is prime.at n=22A275525
- Greatest integer k such that k/2^n < e^2.at n=11A293359
- Numbers m such that beta(m) = tau(m)/2 + 1 where beta(m) is the number of Brazilian representations of m and tau(m) is the number of divisors of m.at n=31A326381
- Non-oblong composites m such that beta(m) = tau(m)/2 + 1 where beta(m) is the number of Brazilian representations of m and tau(m) is the number of divisors of m.at n=29A326388
- Numbers k such that there are exactly 9 numbers j for which binomial(k, floor(k/2)) / binomial(k,j) is an integer, i.e., A080383(k) = 9.at n=5A327431
- Expansion of e.g.f. exp( -LambertW(-2 * sinh(x)) / 2 ).at n=5A381262