Number of the day: 71830

Properties of the number 71830:

71830 = 2 × 5 × 11 × 653 is the 64721^th composite number and is squarefree.
71830 has 4 distinct prime factors, 16 divisors, 15 antidivisors and 26080 totatives.
71830 has a prime digit sum 19 in base 10.
71830 = (167 × 168)/2 + … + (171 × 172)/2 is the sum of at least 2 consecutive triangular numbers in 1 way.
71830 is the sum of 2 positive triangular numbers.
71830 is the difference of 2 positive pentagonal numbers in 3 ways.
71830 = 10² + 21² + 267² is the sum of 3 positive squares.
71830² = 43098² + 57464² = 10032² + 71126² = 29546² + 65472² = 34650² + 62920² is the sum of 2 positive squares in 4 ways.
71830² is the sum of 3 positive squares.
71830 is a proper divisor of 149²⁰ - 1.
71830 is palindromic in (at least) base 84.

The number 71830 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequence (among others):

Sequence number and description below are taken from OEIS.
A022314: a(n) = a(n-1) + a(n-2) + 1, with a(0) = 0, a(1) = 9.