Number of the day: 7868

Properties of the number 7868:

7868 = 2² × 7 × 281 is the 6874^th composite number and is not squarefree.
7868 has 3 distinct prime factors, 12 divisors, 9 antidivisors and 3360 totatives.
7868 has a prime digit sum 29 in base 10.
Reversing the decimal digits of 7868 results in a sphenic number.
7868 = 1968² - 1966² = 288² - 274² is the difference of 2 nonnegative squares in 2 ways.
7868 is the sum of 2 positive triangular numbers.
7868 is the difference of 2 positive pentagonal numbers in 2 ways.
7868 is not the sum of 3 positive squares.
7868² = 4480² + 6468² is the sum of 2 positive squares in 1 way.
7868² is the sum of 3 positive squares.
7868 is a proper divisor of 563⁶ - 1.
7868 is palindromic in (at least) the following bases: 13, 29, 30, 57, -9, -27, -55, and -69.
7868 in base 13 = 3773 and consists of only the digits '3' and '7'.
7868 in base 21 = hhe and consists of only the digits 'e' and 'h'.
7868 in base 26 = bgg and consists of only the digits 'b' and 'g'.
7868 in base 29 = 9a9 and consists of only the digits '9' and 'a'.
7868 in base 30 = 8m8 and consists of only the digits '8' and 'm'.
7868 in base 33 = 77e and consists of only the digits '7' and 'e'.
7868 in base 56 = 2SS and consists of only the digits '2' and 'S'.
7868 in base 57 = 2O2 and consists of only the digits '2' and 'O'.
7868 in base 62 = 22u and consists of only the digits '2' and 'u'.

The number 7868 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A000441: a(n) = Sum_{k=1..n-1} k*sigma(k)*sigma(n-k).
A000716: Number of partitions of n into parts of 3 kinds.
A055437: a(n) = 10*n^2+n.
A065069: Numbers n such that Fibonacci(n) is not squarefree, but for all proper divisors k of n, Fibonacci(k) is squarefree.
A188774: T(n,k)=Number of nXk binary arrays without the pattern 0 1 0 vertically or horizontally
A206368: Numbers n such that A206369(n) = A206039(n+1).
A207100: T(n,k)=Number of 0..k arrays x(0..n-1) of n elements with each no smaller than the sum of its two previous neighbors modulo (k+1)
A231682: a(n) = Sum_{i=0..n} digsum_8(i)^3, where digsum_8(i) = A053829(i).
A240192: T(n,k)=Number of nXk 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of the elements above it or three plus the sum of the elements diagonally to its northwest, modulo 4
A287055: Numbers n such that uphi(n) = uphi(n+1), where uphi(n) is the unitary totient function (A047994).