15085
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 20736
- Proper Divisor Sum (Aliquot Sum)
- 5651
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 10320
- Möbius Function
- -1
- Radical
- 15085
- Omega Function (Ω)
- 3
- 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
- 115
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
- Numbers k such that sigma(k+2) = sigma(k).at n=22A007373
- Numbers whose sum of divisors is a fourth power.at n=39A019422
- When squared gives number composed of digits {2, 5, 7}.at n=6A030487
- a(n) = 10*a(n-1)+n^2, a(0)=0.at n=5A032343
- Numbers k such that A065608(k) = A065608(k+2).at n=12A065064
- a(n) is the first of a triple of consecutive integers, each of which is the product of three distinct primes.at n=35A066509
- Triangle read by rows: T(n,k) is number of (n-k) X k matrices, k=0..n, with nonnegative integer entries and every row and column sum <= 2.at n=48A131235
- Triangle read by rows: T(n,k) is number of (n-k) X k matrices, k=0..n, with nonnegative integer entries and every row and column sum <= 2.at n=51A131235
- Generalized Lucas-Pascal triangle; (11*10^n, 1).at n=31A164851
- Numbers k such that k and k+2 have the same number (A000005) and sum of divisors (A000203).at n=9A229254
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 105", based on the 5-celled von Neumann neighborhood.at n=28A270162
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 203", based on the 5-celled von Neumann neighborhood.at n=28A270727
- Triangle read by rows: T(n,k) is the number of bargraphs of semiperimeter n having k levels. A level in a bargraph is a maximal sequence of two or more adjacent horizontal steps; it is preceded and followed by either an up step or a down step.at n=51A273344
- Numbers n such that the decimal digits of n^2 are all prime.at n=11A275971
- 2nd term of the continued fraction for 2-sqrt(2)^^n, where x^^n denotes tetration.at n=24A280918
- Square array read by upward antidiagonals: T(n, k) is the number of n-ary strings of length k containing 00.at n=41A340156
- The number of quinary strings of length n containing 00.at n=7A351530
- Number of odd-length twice-partitions of n into partitions with all odd parts.at n=21A358823
- Expansion of (x/(8 * (1-x))) * d/dx(theta_3(x)^4).at n=33A374535
- Numbers k such that the sum of the numbers from 1 to k and that from 1 to k+1 share the same sum of divisors.at n=15A375819