9728120805 has 48 divisors (see below), whose sum is σ = 16874626176. Its totient is φ = 4783484160.

The previous prime is 9728120767. The next prime is 9728120827. The reversal of 9728120805 is 5080218279.

It is a Wieferich number.

It is not a de Polignac number, because 9728120805 - 2¹⁵ = 9728088037 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2769000 + ... + 2772510.

It is an arithmetic number, because the mean of its divisors is an integer number (351554712).

Almost surely, 2^9728120805 is an apocalyptic number.

It is an amenable number.

9728120805 is a deficient number, since it is larger than the sum of its proper divisors (7146505371).

9728120805 is a wasteful number, since it uses less digits than its factorization.

9728120805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4638 (or 4625 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 42.

The square root of 9728120805 is about 98631.2364568142. The cubic root of 9728120805 is about 2134.7301554613.

The spelling of 9728120805 in words is "nine billion, seven hundred twenty-eight million, one hundred twenty thousand, eight hundred five".