28721277288 has 288 divisors, whose sum is σ = 89631360000. Its totient is φ = 8291162880.

The previous prime is 28721277281. The next prime is 28721277307. The reversal of 28721277288 is 88277212782.

It is a happy number.

28721277288 is a `hidden beast` number, since 2 + 87 + 212 + 77 + 288 = 666.

It is not an unprimeable number, because it can be changed into a prime (28721277281) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 19958473 + ... + 19959911.

It is an arithmetic number, because the mean of its divisors is an integer number (311220000).

Almost surely, 2^28721277288 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 28721277288, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44815680000).

28721277288 is an abundant number, since it is smaller than the sum of its proper divisors (60910082712).

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

28721277288 is a wasteful number, since it uses less digits than its factorization.

28721277288 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1581 (or 1563 counting only the distinct ones).

The product of its digits is 2809856, while the sum is 54.

The spelling of 28721277288 in words is "twenty-eight billion, seven hundred twenty-one million, two hundred seventy-seven thousand, two hundred eighty-eight".