864036625921 has 12 divisors (see below), whose sum is σ = 1005994154820. Its totient is φ = 739946793600.

The previous prime is 864036625897. The next prime is 864036625961. The reversal of 864036625921 is 129526630468.

It can be written as a sum of positive squares in 2 ways, for example, as 52075240000 + 811961385921 = 228200^2 + 901089^2 .

It is not a de Polignac number, because 864036625921 - 2¹¹ = 864036623873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (864036625961) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7753980 + ... + 7864621.

It is an arithmetic number, because the mean of its divisors is an integer number (83832846235).

Almost surely, 2^864036625921 is an apocalyptic number.

It is an amenable number.

864036625921 is a deficient number, since it is larger than the sum of its proper divisors (141957528899).

864036625921 is a wasteful number, since it uses less digits than its factorization.

864036625921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15619744 (or 15619737 counting only the distinct ones).

The product of its (nonzero) digits is 3732480, while the sum is 52.

The spelling of 864036625921 in words is "eight hundred sixty-four billion, thirty-six million, six hundred twenty-five thousand, nine hundred twenty-one".