Number of the day: 6667

Properties of the number 6667:

6667 = 59 × 113 is semiprime and squarefree.
6667 has 2 distinct prime factors, 4 divisors, 19 antidivisors and 6496 totatives.
6667 has a semiprime digit sum 25 in base 10.
Reversing the decimal digits of 6667 results in an emirpimes.
6667 = 3334² - 3333² = 86² - 27² is the difference of 2 nonnegative squares in 2 ways.
6667 is the sum of 2 positive triangular numbers.
6667 is the difference of 2 positive pentagonal numbers in 1 way.
6667 = 5² + 9² + 81² is the sum of 3 positive squares.
6667² = 885² + 6608² is the sum of 2 positive squares in 1 way.
6667² is the sum of 3 positive squares.
6667 is a divisor of 1061⁸ - 1.
6667 = '6' + '667' is the concatenation of 2 semiprime numbers.
6667 is an emirpimes in (at least) the following bases: 4, 5, 7, 9, 10, 11, 12, 13, 14, 15, 16, 21, 22, 24, 25, 31, 33, 35, 38, 43, 44, 46, 51, 52, 57, 58, 60, 61, 64, 70, 71, 72, 73, 74, 76, 77, 78, 79, 80, 81, 83, 85, 88, 91, 93, 95, 96, and 98.
6667 is palindromic in (at least) the following bases: 2, 30, 66, -6, -49, and -56.
6667 consists of only the digits '6' and '7'.
6667 in base 29 = 7qq and consists of only the digits '7' and 'q'.
6667 in base 30 = 7c7 and consists of only the digits '7' and 'c'.
6667 in base 36 = 557 and consists of only the digits '5' and '7'.
6667 in base 57 = 22t and consists of only the digits '2' and 't'.

The number 6667 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A035349: "DIK" (bracelet, indistinct, unlabeled) transform of A000237.
A051003: Beastly (or hateful) numbers: numbers containing the string 666 in their decimal expansion.
A067275: Number of Fibonacci numbers A000045(k), k <= 10^n, which end in 4.
A080859: a(n) = 6*n^2 + 4*n + 1.
A088797: Numbers n>2 such that n divides the concatenation of n-2 and n-1.
A147993: Sequence S such that 1 is in S and if x is in S, then 6x-1 and 6x+1 are in S.
A237424: Numbers of the form (10^a + 10^b + 1)/3.
A254143: Products of any two not necessarily distinct terms of A237424.
A256292: Numbers which have only digits 6 and 7 in base 10.
A278784: Numbers n such that A000041(n) is of the form 2^7 * k for odd k.