811968642 has 24 divisors (see below), whose sum is σ = 1759814316. Its totient is φ = 270571776.

The previous prime is 811968631. The next prime is 811968659. The reversal of 811968642 is 246869118.

It can be written as a sum of positive squares in 2 ways, for example, as 703787841 + 108180801 = 26529^2 + 10401^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 84298 + ... + 93434.

Almost surely, 2^811968642 is an apocalyptic number.

811968642 is an abundant number, since it is smaller than the sum of its proper divisors (947845674).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

811968642 is a wasteful number, since it uses less digits than its factorization.

811968642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14082 (or 14079 counting only the distinct ones).

The product of its digits is 165888, while the sum is 45.

The square root of 811968642 is about 28495.0634672043. The cubic root of 811968642 is about 932.9243294950.

The spelling of 811968642 in words is "eight hundred eleven million, nine hundred sixty-eight thousand, six hundred forty-two".