16856
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 26
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 37620
- Proper Divisor Sum (Aliquot Sum)
- 20764
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7056
- Möbius Function
- 0
- Radical
- 602
- Omega Function (Ω)
- 6
- 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
- 159
- 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
- Number of sums S of distinct positive integers satisfying S <= n.at n=44A026906
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 11 ones.at n=37A031779
- Sums of distinct powers of 7.at n=36A033044
- Base-7 digits are, in order, the first n terms of the periodic sequence with initial period 1,0,0.at n=5A033143
- Positive numbers having the same set of digits in base 2 and base 7.at n=30A037412
- Sums of 2 distinct powers of 7.at n=12A038481
- Gaps of 9 in sequence A038593 (lower terms).at n=14A038657
- Gaps of 9 in sequence A038593 (upper terms).at n=13A038658
- Numbers whose base-7 representation contains exactly four 0's.at n=18A043396
- Sums of two powers of 7.at n=17A055258
- Triangle read by rows: T(n,k), n >=1, 0 <= k <= C(n,k), = number of n X n symmetric positive definite matrices with 2's on the main diagonal and 1's and 0's elsewhere and with k 1's above the diagonal.at n=85A080858
- Fourth column of (1,5)-Pascal triangle A096940.at n=41A096941
- Coefficients of the A-Rogers mod 14 identity.at n=40A105780
- Number of forests of labeled rooted trees with n nodes, containing exactly 2 trees of height one, all others having height zero.at n=8A133386
- Triangle T(n,k)=number of forests of labeled rooted trees with n nodes, containing exactly k trees of height one, all others having height zero (n>=0, 0<=k<=floor(n/2)).at n=22A133399
- A005195(n) - A005195(n-2).at n=14A144978
- Totally multiplicative sequence with a(p) = 2*(4*p-1) = 8*p-2 for prime p.at n=43A167332
- Sum 7^((k^2+3k)/2) from k=1 to n.at n=1A178190
- a(1) = 2, a(n) = (n-th-even n^3) - (sum of previous terms).at n=27A181509
- Series reversion of (1 - t*x)*log(1 + x) with respect to x.at n=23A198204