15590
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 28080
- Proper Divisor Sum (Aliquot Sum)
- 12490
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6232
- Möbius Function
- -1
- Radical
- 15590
- 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
- 146
- 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
- yes
- Odd
- no
Appears in sequences
- Absolute value of Glaisher's alpha(n).at n=26A002290
- Coordination sequence for Cr3Si, Si position.at n=32A009927
- Number of horizontally convex n-ominoes in which the top row has exactly 1 square, which is not above the rightmost square in the second row.at n=10A049221
- Numbers k such that 263*2^k-1 is prime.at n=13A050890
- Real parts of binomial transform of the Gaussian primes.at n=12A106463
- Indices of 4th powers (of primes) in the 4-almost primes.at n=6A128304
- Number of 6-bead necklaces labeled with numbers -n..n not allowing reversal, with sum zero and first and second differences in -n..n.at n=10A209010
- Numbers that can be expressed as the sum of their first k consecutive arithmetic derivatives for some k > 1.at n=7A216384
- G.f.: Product_{k>0} (1 - x^k)^4 * (1 - (-x)^k)^8.at n=26A225543
- Number of n X 3 0..1 arrays with no element equal to exactly three horizontal or vertical neighbors, with new values 0..1 introduced in row major order.at n=5A240631
- Number of nX6 0..1 arrays with no element equal to exactly three horizontal or vertical neighbors, with new values 0..1 introduced in row major order.at n=2A240634
- T(n,k)=Number of nXk 0..1 arrays with no element equal to exactly three horizontal or vertical neighbors, with new values 0..1 introduced in row major order.at n=30A240636
- T(n,k)=Number of nXk 0..1 arrays with no element equal to exactly three horizontal or vertical neighbors, with new values 0..1 introduced in row major order.at n=33A240636
- a(n) = the smallest integer k where there are exactly n primes between 10k and 10k+100.at n=1A279862
- Trajectory of 5 under repeated application of x -> A306938(x).at n=15A306943
- Triangle read by rows where T(n,k) is the number of set partitions of {1..n} with exactly k distinct block-sums.at n=61A371788
- Array read by antidiagonals: T(n,k) is the index of prime(k)^n in the numbers with n prime factors, counted with multiplicity.at n=48A376479
- a(n) is the least number that occurs exactly n times in A075255.at n=11A385964