Number of the day: 719628

Happy Pythagorean Theorem Day!

Properties of the number 719628:

719628 = 2² × 3 × 7 × 13 × 659 is the 661629^th composite number and is not squarefree.
719628 has 5 distinct prime factors, 48 divisors, 19 antidivisors and 189504 totatives.
719628 has a semiprime digit sum 33 in base 10.
719628 = 179908² - 179906² = 59972² - 59966² = 25708² - 25694² = 13852² - 13826² = 8588² - 8546² = 4652² - 4574² = 2068² - 1886² = 932² - 386² is the difference of 2 nonnegative squares in 8 ways.
719628 is the difference of 2 positive pentagonal numbers in 3 ways.
719628 = 106² + 214² + 814² is the sum of 3 positive squares.
719628² = 276780² + 664272² is the sum of 2 positive squares in 1 way.
719628² is the sum of 3 positive squares.
719628 is a proper divisor of 1319¹² - 1.

The number 719628 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A241576: Third differences of A001521.
A244020: Number of new points at the n-th step of the following iteration, starting with four points in general position in the real projective plane: dualize the current pointset to a family of lines, take all intersections of those lines, repeat.