16445
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 24192
- Proper Divisor Sum (Aliquot Sum)
- 7747
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 10560
- Möbius Function
- 1
- Radical
- 16445
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 4
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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 40
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
- Odd numbers in the (1,2)-Pascal triangle A029635 that are different from 1.at n=56A029639
- Distinct odd numbers in the (1,2)-Pascal triangle A029635.at n=46A029642
- Numbers to the left of the central elements of the (1,2)-Pascal triangle A029635 that are different from 1.at n=55A029645
- Odd numbers to the left of the central elements of the (1,2)-Pascal triangle A029635.at n=40A029646
- Distinct odd numbers in (2,1)-Pascal triangle A029653.at n=49A029660
- Numbers to the right of the central elements of the (2,1)-Pascal triangle A029653 that are different from 1.at n=49A029663
- Odd numbers to the right of the central elements of the (2,1)-Pascal triangle A029653 that are different from 1.at n=18A029668
- Number of bracelets (turnover necklaces) of n beads of 2 colors, 5 of them black.at n=42A032279
- Number of partitions of n into parts not of the form 25k, 25k+8 or 25k-8. Also number of partitions with at most 7 parts of size 1 and differences between parts at distance 11 are greater than 1.at n=36A036007
- 1/256 of tenth unsigned column of triangle A053120 (T-Chebyshev, rising powers, zeros omitted).at n=7A054333
- Number of 3-element ordered antichain covers of an unlabeled n-element set.at n=10A056074
- Product of next n numbers divided by the largest factorial divisor.at n=6A094336
- Delete first column (index 0) and all rows having nonprime index of triangle T(p,k) defined in A034807 (coefficients of Lucas polynomials). Sequence gives resulting sub-triangle read by rows.at n=41A096539
- Number of permutations of n elements whose unsigned reversal distance is k.at n=32A115755
- Number of positive clusters of type D_n.at n=8A129869
- Sum of root degrees of all symmetric ordered trees with n edges.at n=14A143360
- Number of intersection points outside the n-gon of all lines through pairs of vertices of a regular n-gon.at n=20A146213
- 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, 1, 0), (1, 0, 0), (1, 1, 1)}.at n=7A151110
- Years >= 1801 in which Christmas falls in Sukkot.at n=13A222419
- Composite squarefree numbers k such that the arithmetic mean of the distinct prime factors of k is a prime p, and p divides k.at n=28A229094