15406
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 23112
- Proper Divisor Sum (Aliquot Sum)
- 7706
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7702
- Möbius Function
- 1
- Radical
- 15406
- 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
- 146
- 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
- yes
- Odd
- no
Appears in sequences
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 66 ones.at n=21A031834
- a(n) = 10*n^2 + 5*n + 1.at n=39A080860
- a(n) = 6^n mod 5^n.at n=6A138649
- Number of binary strings of length n with no substrings equal to 0001, 0100, or 0111.at n=18A164464
- Numbers k that are the products of two distinct primes such that 2*k-1, 4*k-3, 8*k-7, 16*k-15 and 32*k-31 are also products of two distinct primes.at n=25A177214
- Semiprimes that are the sum of 10 consecutive primes.at n=19A185347
- Smallest positive even number in the sequence (k+1)^n (mod k^n) for k=1,2,3....at n=3A188699
- Expansion of (eta(q^5) * eta(q^10) / (eta(q) * eta(q^2)))^2 in powers of q.at n=15A227213
- Number of (n+2)X(1+2) 0..1 arrays with no 3x3 subblock diagonal sum 0 and no antidiagonal sum 0 and no row sum 1 and no column sum 1.at n=6A255142
- Number of (n+2)X(7+2) 0..1 arrays with no 3x3 subblock diagonal sum 0 and no antidiagonal sum 0 and no row sum 1 and no column sum 1.at n=0A255148
- T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with no 3x3 subblock diagonal sum 0 and no antidiagonal sum 0 and no row sum 1 and no column sum 1.at n=21A255149
- T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with no 3x3 subblock diagonal sum 0 and no antidiagonal sum 0 and no row sum 1 and no column sum 1.at n=27A255149
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 73", based on the 5-celled von Neumann neighborhood.at n=27A270089
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 73", based on the 5-celled von Neumann neighborhood.at n=28A270089
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 165", based on the 5-celled von Neumann neighborhood.at n=27A270459
- Number of permutations of [n] with at least one hit on both main diagonals.at n=8A378907
- Centered pentagonal numbers which are squarefree semiprimes.at n=30A381043
- Centered pentagonal numbers which are semiprimes.at n=30A382132