Number of the day: 18879

Properties of the number 18879:

18879 = 3 × 7 × 29 × 31 is the 16729^th composite number and is squarefree.
18879 has 4 distinct prime factors, 16 divisors, 19 antidivisors and 10080 totatives.
18879 has a semiprime digit sum 33 in base 10.
18879 has an oblong digit product 4032 in base 10.
18879 = 30² + … + 43² = 8² + … + 38² is the sum of at least 2 consecutive positive squares in 2 ways.
18879 = 9440² - 9439² = 3148² - 3145² = 1352² - 1345² = 460² - 439² = 340² - 311² = 320² - 289² = 152² - 65² = 148² - 55² is the difference of 2 nonnegative squares in 8 ways.
18879 is the sum of 2 positive triangular numbers.
18879 is the difference of 2 positive pentagonal numbers in 3 ways.
18879 is not the sum of 3 positive squares.
18879² = 13020² + 13671² is the sum of 2 positive squares in 1 way.
18879² is the sum of 3 positive squares.
18879 is a proper divisor of 347⁶ - 1.
18879 is palindromic in (at least) the following bases: 78, -36, and -56.
18879 in base 6 = 223223 and consists of only the digits '2' and '3'.
18879 in base 35 = fee and consists of only the digits 'e' and 'f'.

The number 18879 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A015636: Number of ordered quadruples of integers from [ 1,n ] with no common factors between pairs.
A060578: Number of homeomorphically irreducible general graphs on 3 labeled node and with n edges.
A062681: Numbers that are sums of 2 or more consecutive squares in more than 1 way.
A130014: Nonnegative values x of solutions (x, y) to the Diophantine equation x^2+(x+881)^2 = y^2.
A130052: Numbers that are the sum of one or more consecutive squares in more than one way.
A138693: Numbers of the form 110 + p^2. (where p is a prime).
A262408: Positive integers m such that pi(m^2) = pi(j^2) + pi(k^2) for no 0 < j <= k < m.
A304469: Number of nX5 0..1 arrays with every element unequal to 0, 1, 2, 3 or 6 king-move adjacent elements, with upper left element zero.
A304470: Number of nX6 0..1 arrays with every element unequal to 0, 1, 2, 3 or 6 king-move adjacent elements, with upper left element zero.
A304472: T(n,k)=Number of nXk 0..1 arrays with every element unequal to 0, 1, 2, 3 or 6 king-move adjacent elements, with upper left element zero.