Number of the day: 67866

Marius Sophus Lie was born on this day 176 years ago.

Properties of the number 67866:

67866 = 2 × 3 × 11311 is a sphenic number and squarefree.
67866 has 3 distinct prime factors, 8 divisors, 9 antidivisors and 22620 totatives.
67866 has a semiprime digit sum 33 in base 10.
67866 is the sum of 2 positive triangular numbers.
67866 = 56² + 61² + 247² is the sum of 3 positive squares.
67866² is the sum of 3 positive squares.
67866 is a proper divisor of 967¹³ - 1.
67866 = '678' + '66' is the concatenation of 2 sphenic numbers.
67866 = '6786' + '6' is the concatenation of 2 triangular numbers.
67866 in base 12 = 33336 and consists of only the digits '3' and '6'.

The number 67866 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequence (among others):

Sequence number and description below are taken from OEIS.
A104268: a(n) = 2*4^(n-1) - (3n-1)/(2n+2)*C(2n,n).