28787878782 has 72 divisors (see below), whose sum is σ = 67594184424. Its totient is φ = 8850808512.

The previous prime is 28787878697. The next prime is 28787878783.

28787878782 is nontrivially palindromic in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 28787878782.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28787878783) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 4903813 + ... + 4909679.

It is an arithmetic number, because the mean of its divisors is an integer number (938808117).

Almost surely, 2^28787878782 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28787878782, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33797092212).

28787878782 is an abundant number, since it is smaller than the sum of its proper divisors (38806305642).

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

28787878782 is a wasteful number, since it uses less digits than its factorization.

28787878782 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7514 (or 7498 counting only the distinct ones).

The product of its digits is 314703872, while the sum is 72.

The spelling of 28787878782 in words is "twenty-eight billion, seven hundred eighty-seven million, eight hundred seventy-eight thousand, seven hundred eighty-two".