15964
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 25
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 30184
- Proper Divisor Sum (Aliquot Sum)
- 14220
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7344
- Möbius Function
- 0
- Radical
- 7982
- 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
- 53
- 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 k | 12^k + 12.at n=27A015904
- First row of spectral array W(e-1).at n=22A022161
- Sin(n) decreases monotonically to -1.at n=27A046964
- a(0)=1; a(n) is the smallest integer > a(n-1) such that sin(a(n)) is closer to an integer (here 0 or -1) than sin(a(n-1)).at n=26A079037
- 2*3*5*6*...*a(n) -+ 1 are primes, with a(n+1) > a(n).at n=40A087900
- Even pseudoprimes to base 9.at n=22A090083
- a(n) = 997*n + 1009.at n=15A100776
- Expansion of g.f.: 1/((1 - x - x^2 + x^5 - x^7)*(1 - x^2 + x^5 + x^6 - x^7)).at n=22A147617
- 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, 0, 0), (0, 1, 1), (1, -1, 0), (1, 1, -1)}.at n=9A148939
- a(1) = 1, and for each k >=2, a(k) is the smallest number n such that n/cos(n) > a(k)/cos(a(k)), so that a(1)/cos(a(1)) > a(2)/cos(a(2)) > ... > a(k)/cos(a(k)) > ...at n=37A172446
- a(1) = 1, and for each n >=2, a(n) is the smallest number such that 1/cos(a(n)) < 1/cos(k) for all k < n, so that 1/cos(a(1)) > 1/cos(a(2)) > ... > 1/cos(a(n)) > ...at n=26A172448
- Numbers k such that, taken together, the base-10 and base-b expansions of k are pandigital for some b < 10.at n=3A174596
- Numbers k such that 2^k + k^2 - 1 is prime.at n=12A215439
- Number of (n+2)X(3+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000001 00001001 or 00100101.at n=8A260975
- Expansion of Product_{k>=1} 1/(1 - x^(2*k+1))^k.at n=42A263150
- Even 14-gonal (or tetradecagonal) numbers.at n=26A270704
- Expansion of 1/(1 - Sum_{k>=1} mu(2*k-1)^2*x^(2*k-1)), where mu() is the Moebius function (A008683).at n=22A280198
- Pseudoprimes to base 9 that are not squarefree.at n=22A306448
- Smallest numbers leading in n steps to a term that repeats itself, according to the rule explained in A316650 (and hereunder in the Comment section).at n=44A316678
- Number of partitions of n with nine parts in which no part occurs more than twice.at n=35A320597