8721578723 has 24 divisors (see below), whose sum is σ = 10338032544. Its totient is φ = 7308829440.

The previous prime is 8721578707. The next prime is 8721578737. The reversal of 8721578723 is 3278751278.

It is not a de Polignac number, because 8721578723 - 2⁴ = 8721578707 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8721578743) 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, 1291211 + ... + 1297947.

It is an arithmetic number, because the mean of its divisors is an integer number (430751356).

Almost surely, 2^8721578723 is an apocalyptic number.

8721578723 is a deficient number, since it is larger than the sum of its proper divisors (1616453821).

8721578723 is a wasteful number, since it uses less digits than its factorization.

8721578723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7595 (or 7584 counting only the distinct ones).

The product of its digits is 1317120, while the sum is 50.

The square root of 8721578723 is about 93389.3929897823. The cubic root of 8721578723 is about 2058.4091405468.

The spelling of 8721578723 in words is "eight billion, seven hundred twenty-one million, five hundred seventy-eight thousand, seven hundred twenty-three".