8721039864 has 32 divisors (see below), whose sum is σ = 21836545920. Its totient is φ = 2902487136.

The previous prime is 8721039863. The next prime is 8721039869. The reversal of 8721039864 is 4689301278.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8721039863) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 267132 + ... + 297995.

It is an arithmetic number, because the mean of its divisors is an integer number (682392060).

Almost surely, 2^8721039864 is an apocalyptic number.

It is an amenable number.

8721039864 is an abundant number, since it is smaller than the sum of its proper divisors (13115506056).

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

8721039864 is a wasteful number, since it uses less digits than its factorization.

8721039864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 565779 (or 565775 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 48.

The square root of 8721039864 is about 93386.5079334269. The cubic root of 8721039864 is about 2058.3667470318.

The spelling of 8721039864 in words is "eight billion, seven hundred twenty-one million, thirty-nine thousand, eight hundred sixty-four".