16948
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 28
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 31360
- Proper Divisor Sum (Aliquot Sum)
- 14412
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7992
- Möbius Function
- 0
- Radical
- 8474
- Omega Function (Ω)
- 4
- 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
- 35
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
- a(0) = 0; for n>0, a(n) = maximal number of regions into which space can be divided by n spheres.at n=38A046127
- Number of irregular primes less than 2^n.at n=18A105456
- Number of parts in all partitions of n in which every integer from the smallest part to the largest part occurs as a part.at n=37A117457
- Sums of NE-SW diagonals of triangle A172171.at n=18A172173
- Regular triangle, T(n, k) = f(n, k) - f(n, 0) + 1, where f(n, k) = Sum_{j=0..k} StirlingS2(n, n-j)*binomial(n,j) + Sum_{j=0..n-k} StirlingS2(n, n-j)*binomial(n, j), read by rows.at n=47A176157
- Regular triangle, T(n, k) = f(n, k) - f(n, 0) + 1, where f(n, k) = Sum_{j=0..k} StirlingS2(n, n-j)*binomial(n,j) + Sum_{j=0..n-k} StirlingS2(n, n-j)*binomial(n, j), read by rows.at n=52A176157
- Number of permutations of 0..(n-1) representable as consecutive sums of 6 adjacent elements of a sequence of n+5 nonnegative integers.at n=12A180209
- Number of distinct nonnegative integers that can be generated by an expression containing n binary operators (any of add, subtract, multiply and divide) whose operands are any integer between 1 and 9; parenthesis allowed.at n=5A181960
- Triangle read by rows of operator ordering coefficients corresponding to the Hermite polynomials H_n(x).at n=24A225695
- Triangle read by rows: T(m,n) is the label of the largest square that an (m,n)-leaper (a generalization of a chess knight) reaches before it can no longer move, starting on a board with squares spirally numbered, starting at 1; 1 <= n < m. Each move is to the lowest-numbered unvisited square.at n=31A306197
- Numbers k such that the k-th composition in standard order is a permutation (of an initial interval).at n=39A333218
- Numbers that are the sum of nine fourth powers in exactly ten ways.at n=36A345852
- Numbers k such that the k-th composition in standard order is a non-alternating permutation of an initial interval of positive integers.at n=21A350250
- Numbers k such that 3^(k-1) - 2^k is prime.at n=28A363375