16431
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 21912
- Proper Divisor Sum (Aliquot Sum)
- 5481
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 10952
- Möbius Function
- 1
- Radical
- 16431
- 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
- 221
- 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
- Expansion of 1/((1-x^2)*(1-x^4)^2*(1-x^6)*(1-x^8)*(1-x^10)) (even powers only).at n=46A001994
- Ceiling of Gamma(n+7/10)/Gamma(7/10).at n=8A020106
- Number of partitions of n into parts having at most two prime-factors.at n=37A101049
- Number of Barlow packings that repeat after n (or a divisor of n) layers.at n=21A114438
- a(n) = (n^3 + 3*n - 2)/2.at n=31A132127
- Number of n X n binary arrays symmetric under horizontal reflection with all ones connected only in a 101-111-101 pattern in any orientation.at n=10A146430
- Numbers n with property that n^2 is a concatenation of three 3-digit primes.at n=21A153139
- Numbers k such that 11^k + 3^k - 1 is prime.at n=9A177030
- Minimal number (in decimal representation) with n nonprime substrings in base-4 representation (substrings with leading zeros are considered to be nonprime).at n=31A217104
- Exponents m such that the decimal expansion of 5^m exhibits its first zero from the right later than any previous exponent.at n=20A239010
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 621", based on the 5-celled von Neumann neighborhood.at n=23A273268
- Numbers k such that (58*10^k + 419)/9 is prime.at n=19A294526
- Number of nX5 0..1 arrays with every element unequal to 0, 2, 3 or 4 king-move adjacent elements, with upper left element zero.at n=6A303885
- Number of nX7 0..1 arrays with every element unequal to 0, 2, 3 or 4 king-move adjacent elements, with upper left element zero.at n=4A303887
- T(n,k)=Number of nXk 0..1 arrays with every element unequal to 0, 2, 3 or 4 king-move adjacent elements, with upper left element zero.at n=59A303888
- Triangle read by rows: T(n,k) is the number of unsensed combinatorial maps with n edges and k vertices, 1 <= k <= n + 1.at n=29A380616
- Number of unsensed combinatorial maps with n edges and 2 vertices.at n=6A380620
- a(n) = (smallest digit of n)^(largest digit of n) + n.at n=47A386253