Wednesday, May 11, 2016

Number of the day: 69891

Properties of the number 69891:

69891 = 3 × 23297 is semiprime and squarefree.
69891 has 2 distinct prime factors, 4 divisors, 11 antidivisors and 46592 totatives.
69891 has a semiprime digit sum 33 in base 10.
69891 = 349462 - 349452 = 116502 - 116472 is the difference of 2 nonnegative squares in 2 ways.
69891 is the difference of 2 positive pentagonal numbers in 1 way.
69891 = 312 + 892 + 2472 is the sum of 3 positive squares.
698912 = 223652 + 662162 is the sum of 2 positive squares in 1 way.
698912 is the sum of 3 positive squares.
69891 is a divisor of 31732 - 1.
69891 = '698' + '91' is the concatenation of 2 semiprime numbers.
69891 is an emirpimes in (at least) the following bases: 3, 5, 13, 15, 23, 26, 37, 39, 40, 42, 49, 54, 59, 60, 63, 67, 69, 71, 75, 81, 84, 91, 94, and 97.
69891 is palindromic in (at least) the following bases: 12, and 65.

The number 69891 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequence (among others):

Sequence number and description below are taken from OEIS.
A246797: Triangle read by rows: T(n,k) is the coefficient A_k in the transformation Sum_{k=0..n} (k+1)*x^k = Sum_{k=0..n} A_k*(x-2)^k.

No comments:

Post a Comment