879533397821 has 24 divisors (see below), whose sum is σ = 984966097752. Its totient is φ = 780681283200.

The previous prime is 879533397817. The next prime is 879533397871. The reversal of 879533397821 is 128793335978.

879533397821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 49956720100 + 829576677721 = 223510^2 + 910811^2 .

It is not a de Polignac number, because 879533397821 - 2² = 879533397817 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (879533397811) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1737191 + ... + 2185611.

It is an arithmetic number, because the mean of its divisors is an integer number (41040254073).

Almost surely, 2^879533397821 is an apocalyptic number.

It is an amenable number.

879533397821 is a deficient number, since it is larger than the sum of its proper divisors (105432699931).

879533397821 is a wasteful number, since it uses less digits than its factorization.

879533397821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 448653 (or 448622 counting only the distinct ones).

The product of its digits is 68584320, while the sum is 65.

The spelling of 879533397821 in words is "eight hundred seventy-nine billion, five hundred thirty-three million, three hundred ninety-seven thousand, eight hundred twenty-one".