15381
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 22230
- Proper Divisor Sum (Aliquot Sum)
- 6849
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 10248
- Möbius Function
- 0
- Radical
- 5127
- 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
- yes
- 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
- no
- Odd
- yes
Appears in sequences
- Number of achiral rooted trees.at n=26A003241
- Numerators of continued fraction convergents to sqrt(314).at n=7A041592
- Numbers k such that prime(k+3)-(k+3)*tau(k+3) = prime(k-3)-(k-3)*tau(k-3) where tau(k) = A000005(k) is the number of divisors of k.at n=34A067355
- Number of base 11 n-digit numbers with adjacent digits differing by three or less.at n=5A126479
- Number of graphs on n labeled nodes with maximal degree exactly 4.at n=5A136286
- (n-1)-st elementary symmetric function of {1,3,7,15,31,63,...-1+2^n}.at n=4A203011
- Number of (n+2)X(5+2) 0..1 arrays with every 3X3 subblock sum of the two sums of the diagonal and antidiagonal minus the two minimums of the central column and central row nondecreasing horizontally, vertically and ne-to-sw antidiagonally.at n=25A254904
- Numbers n for which the numbers 6n+1, 3n+2, 6n+7 are all odd composite squarefree numbers, but none are semiprimes.at n=21A263510
- Numbers k such that (85*10^k - 1)/3 is prime.at n=18A289942
- Numbers k such that 455*2^k+1 is prime.at n=23A323197
- Terms k of A228058 such that gcd(k - A048250(k), A162296(k) - k) = A162296(k) - k.at n=26A325376
- Numbers k in A228058 such that also A001065(k) is in A228058.at n=22A325380
- Number of labeled simple graphs covering n vertices with at least one endpoint/leaf.at n=6A327227
- Triangle read by rows where T(n,k) is the number of labeled simple graphs with n vertices and minimum vertex-degree k.at n=22A327366
- Triangle read by rows, matrix inverse of A139382.at n=16A342186
- Consecutive states of the linear congruential pseudo-random number generator (10924*s+11830) mod (2^15+1) when started at s=1.at n=29A384150
- Odd composites k such that sigma(k) has the same powerful part as k, where sigma is the sum of divisors function.at n=15A386425