28390728897 has 12 divisors (see below), whose sum is σ = 41049088080. Its totient is φ = 18908572248.

The previous prime is 28390728893. The next prime is 28390728907. The reversal of 28390728897 is 79882709382.

It is a happy number.

It is not a de Polignac number, because 28390728897 - 2² = 28390728893 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28390728893) 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, 1538683 + ... + 1557024.

It is an arithmetic number, because the mean of its divisors is an integer number (3420757340).

Almost surely, 2^28390728897 is an apocalyptic number.

It is an amenable number.

28390728897 is a deficient number, since it is larger than the sum of its proper divisors (12658359183).

28390728897 is a wasteful number, since it uses less digits than its factorization.

28390728897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3096732 (or 3096729 counting only the distinct ones).

The product of its (nonzero) digits is 24385536, while the sum is 63.

The spelling of 28390728897 in words is "twenty-eight billion, three hundred ninety million, seven hundred twenty-eight thousand, eight hundred ninety-seven".