28721850912 has 120 divisors (see below), whose sum is σ = 84594717900. Its totient is φ = 9559835136.

The previous prime is 28721850901. The next prime is 28721850929. The reversal of 28721850912 is 21905812782.

It can be written as a sum of positive squares in 2 ways, for example, as 27890336016 + 831514896 = 167004^2 + 28836^2 .

It is a super-2 number, since 2×28721850912² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 1829914 + ... + 1845542.

Almost surely, 2^28721850912 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 28721850912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42297358950).

28721850912 is an abundant number, since it is smaller than the sum of its proper divisors (55872866988).

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

28721850912 is a wasteful number, since it uses less digits than its factorization.

28721850912 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16360 (or 16343 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 45.

The spelling of 28721850912 in words is "twenty-eight billion, seven hundred twenty-one million, eight hundred fifty thousand, nine hundred twelve".