15817864868 has 24 divisors (see below), whose sum is σ = 29825482680. Its totient is φ = 7296906240.

The previous prime is 15817864831. The next prime is 15817864963. The reversal of 15817864868 is 86846871851.

It can be written as a sum of positive squares in 4 ways, for example, as 4583560804 + 11234304064 = 67702^2 + 105992^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 15817864868.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30548 + ... + 180468.

It is an arithmetic number, because the mean of its divisors is an integer number (1242728445).

Almost surely, 2^15817864868 is an apocalyptic number.

It is an amenable number.

15817864868 is a deficient number, since it is larger than the sum of its proper divisors (14007617812).

15817864868 is a wasteful number, since it uses less digits than its factorization.

15817864868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 151967 (or 151965 counting only the distinct ones).

The product of its digits is 20643840, while the sum is 62.

The spelling of 15817864868 in words is "fifteen billion, eight hundred seventeen million, eight hundred sixty-four thousand, eight hundred sixty-eight".