28785769728 has 144 divisors (see below), whose sum is σ = 81668428800. Its totient is φ = 8974817280.

The previous prime is 28785769723. The next prime is 28785769751. The reversal of 28785769728 is 82796758782.

Its product of digits (189665280) is a multiple of the sum of its prime factors (25088).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28785769723) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1140283 + ... + 1165253.

Almost surely, 2^28785769728 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28785769728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40834214400).

28785769728 is an abundant number, since it is smaller than the sum of its proper divisors (52882659072).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28785769728 is a wasteful number, since it uses less digits than its factorization.

28785769728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25088 (or 25074 counting only the distinct ones).

The product of its digits is 189665280, while the sum is 69.

The spelling of 28785769728 in words is "twenty-eight billion, seven hundred eighty-five million, seven hundred sixty-nine thousand, seven hundred twenty-eight".