15697
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 28
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 17136
- Proper Divisor Sum (Aliquot Sum)
- 1439
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 14260
- Möbius Function
- 1
- Radical
- 15697
- Omega Function (Ω)
- 2
- 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
- 177
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- 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 partitions of n into parts not of the form 23k, 23k+4 or 23k-4. Also number of partitions with at most 3 parts of size 1 and differences between parts at distance 10 are greater than 1.at n=38A035992
- Indices of primes in sequence defined by A(0) = 11, A(n) = 10*A(n-1) + 21 for n > 0.at n=11A056244
- Semiprimes in A056109.at n=31A113528
- First string of 43 consecutive composite numbers.at n=13A177949
- Diagonal sums of the Riordan matrix A104259.at n=8A190737
- Number of partitions of n such that the m(number of distinct parts) is a part, where m = multiplicity.at n=42A240307
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 181", based on the 5-celled von Neumann neighborhood.at n=27A270628
- Numbers k such that 4*10^k + 19 is prime.at n=28A271548
- Number of n X 4 0..1 arrays with every element unequal to 0, 1, 2, 4 or 7 king-move adjacent elements, with upper left element zero.at n=7A304844
- Square array T(n,k), n >= 1, k >= 1, read by antidiagonals, where T(n,k) = Sum_{1 <= x_1, x_2, ..., x_k <= n} gcd(x_1, x_2, ..., x_k).at n=49A344479
- Greedy Cantor's Dust Partition.at n=45A348636
- a(n) = A276086(n) - n, where A276086 is the primorial base exp-function.at n=53A351225
- Semiprimes k such that k+4, k+6, k+9, k+10 and k+14 are also semiprimes.at n=3A360666
- Numbers k such that k + 4, k + 6, k + 9, k + 10, and k + 14 are all semiprimes, where 4, 6, 9, 10, 14 are the first 5 semiprimes.at n=13A365240
- a(n) = 12*n^2 + 4*n + 1.at n=36A381390