28921989696 has 224 divisors, whose sum is σ = 82258936320. Its totient is φ = 8941363200.

The previous prime is 28921989661. The next prime is 28921989713. The reversal of 28921989696 is 69698912982.

It is a self number, because there is not a number n which added to its sum of digits gives 28921989696.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 58904011 + ... + 58904501.

Almost surely, 2^28921989696 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 28921989696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41129468160).

28921989696 is an abundant number, since it is smaller than the sum of its proper divisors (53336946624).

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

28921989696 is a wasteful number, since it uses less digits than its factorization.

28921989696 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 833 (or 823 counting only the distinct ones).

The product of its digits is 60466176, while the sum is 69.

The spelling of 28921989696 in words is "twenty-eight billion, nine hundred twenty-one million, nine hundred eighty-nine thousand, six hundred ninety-six".