28928913 has 12 divisors (see below), whose sum is σ = 41767920. Its totient is φ = 17802096.

The previous prime is 28928897. The next prime is 28928941. The reversal of 28928913 is 31982982.

It is not a de Polignac number, because 28928913 - 2⁴ = 28928897 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28928953) 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, 28023 + ... + 29036.

It is an arithmetic number, because the mean of its divisors is an integer number (3480660).

Almost surely, 2^28928913 is an apocalyptic number.

It is an amenable number.

28928913 is a deficient number, since it is larger than the sum of its proper divisors (12839007).

28928913 is a wasteful number, since it uses less digits than its factorization.

28928913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57088 (or 57075 counting only the distinct ones).

The product of its digits is 62208, while the sum is 42.

The square root of 28928913 is about 5378.5604951511. The cubic root of 28928913 is about 306.9804406330.

The spelling of 28928913 in words is "twenty-eight million, nine hundred twenty-eight thousand, nine hundred thirteen".