8921568728 has 8 divisors (see below), whose sum is σ = 16727941380. Its totient is φ = 4460784360.

The previous prime is 8921568713. The next prime is 8921568743. The reversal of 8921568728 is 8278651298.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (8921568713) and next prime (8921568743).

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 557598038 + ... + 557598053.

Almost surely, 2^8921568728 is an apocalyptic number.

It is an amenable number.

8921568728 is a deficient number, since it is larger than the sum of its proper divisors (7806372652).

8921568728 is a wasteful number, since it uses less digits than its factorization.

8921568728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1115196097 (or 1115196093 counting only the distinct ones).

The product of its digits is 3870720, while the sum is 56.

The square root of 8921568728 is about 94454.0561754761. The cubic root of 8921568728 is about 2074.0238290660.

The spelling of 8921568728 in words is "eight billion, nine hundred twenty-one million, five hundred sixty-eight thousand, seven hundred twenty-eight".