15554
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
- 2
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 29376
- Proper Divisor Sum (Aliquot Sum)
- 13822
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6000
- Möbius Function
- 1
- Radical
- 15554
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 4
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
- 84
- 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
- Number of points on surface of hexagonal prism: 12*n^2 + 2 for n > 0 (coordination sequence for W(2)).at n=36A005914
- a(0) = 1, a(n) = 27*n^2 + 2 for n>0.at n=24A010017
- Numbers having four 0's in base 6.at n=31A043372
- Numbers with exactly 4 distinct palindromic prime factors.at n=35A046402
- Convolution of the prime numbers with phi(n).at n=34A086734
- Number of points in the standard root system version of the D_3 (or f.c.c.) lattice having L_infinity norm n.at n=36A110907
- Exponent of least power of 2 having exactly n consecutive 9's in its decimal representation.at n=7A131543
- Numbers k such that k and k+1 have 4 distinct prime factors.at n=13A140078
- Number of ways of placing kings with no more than 4 mutual attacks on an n X n chessboard symmetric under 90-degree rotation.at n=10A143892
- Twice repdigit numbers.at n=34A152966
- a(n) = floor(n^(n^(1/3))).at n=25A157254
- Difference A063990(2n)-A063990(2n-1) between amicable numbers.at n=17A178542
- Number of n-bead necklaces labeled with numbers -1..1 not allowing reversal, with sum zero with no three beads in a row equal.at n=13A208938
- Triangle where the g.f. of row n is: Sum_{k=0..n^2-n+1} T(n,k)*y^k = (2*(1+y)^n - 1) * ((1+y)^n - 1)^(n-1) / y^(n-1), as read by rows.at n=21A220265
- Numbers k having at least two complementary pairs of divisors (q, p) and (p', q') such that k = p*q = p'*q' where the decimal digits of p' are the 9's complement of the decimal digits of p and the decimal digits of q' are the 9's complement of the decimal digits of q.at n=10A226587
- Number of tuples (x_1, x_2, ..., x_n) with 1 <= x_1 <= x_2 <= ... <= x_n such that Sum_{i=1..n} x_i^3 = (Sum_{i=1..n} x_i)^2 and Sum_{i=1..n-1} x_i^3 + (x_n-1)^3 + (x_n+1)^3 = (Sum_{i=1..n-1} x_i + 2x_n)^2.at n=15A227847
- The number of sum indecomposable permutations which avoid the patterns 3124 and 4312.at n=8A228770
- Number of partitions p of n such that (number of even numbers in p) < 2*(number of odd numbers in p).at n=36A241641
- Numbers which are divisible by prime(d) for all digits d in their decimal representation.at n=34A256786
- Numbers k, the smallest of at least 4 consecutive numbers x, for which phi(x) <= phi(x+1).at n=47A295865