15553
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
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 15808
- Proper Divisor Sum (Aliquot Sum)
- 255
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 15300
- Möbius Function
- 1
- Radical
- 15553
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 84
- 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
- a(n+1) = a(n) converted to base 9 from base 5 (written in base 10).at n=8A023382
- Numbers having four 0's in base 6.at n=30A043372
- Counterbalanced numbers: Composite numbers k such that phi(k)/(sigma(k)-k) is an integer.at n=20A055940
- a(n) = 2*prime(n)^2 - prime(n+1)^2.at n=31A064051
- a(n) = 15*n^2 + 6*n + 1.at n=32A080861
- Schmidt's problem sum for r = 5.at n=2A092815
- Table, read by antidiagonals, of iterated binomial transforms of A095148, which also forms the antidiagonal sums shift right.at n=53A095788
- Pierpont semiprimes: semiprimes of the form (2^K)*(3^L)+1.at n=31A113432
- Semiprimes in A056107.at n=20A113525
- Column 2 of triangle A128545; a(n) is the coefficient of q^(2n+4) in the central q-binomial coefficient [2n+4,n+2].at n=16A128552
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (-1, 1, 0), (0, 0, 1), (0, 1, -1), (1, 0, 0)}.at n=8A150074
- a(n) = 576*n + 1.at n=26A158370
- a(n) = 12*n^2 + 1.at n=36A158480
- a(n) = 48*n^2 + 1.at n=18A158638
- Partial sums of Proth primes A080076.at n=22A172243
- Semiprimes which are the sum of three distinct positive cubes in two or more distinct ways.at n=17A180089
- a(n) = 2*6^n + 1.at n=5A199317
- a(n) = Sum_{i=1..n} ( Product_{k|i} d(k) ), where d(n) = A000005(n).at n=34A237349
- Number of partitions p of n such that median(p) = multiplicity(max(p)).at n=43A240209
- Semiprimes of the form p^2 + pq + q^2, where p, q are consecutive primes.at n=9A243904