28791784379925 has 108 divisors (see below), whose sum is σ = 60539118122340. Its totient is φ = 13041206115840.

The previous prime is 28791784379863. The next prime is 28791784379927. The reversal of 28791784379925 is 52997348719782.

28791784379925 is a `hidden beast` number, since 2 + 8 + 7 + 9 + 1 + 78 + 437 + 99 + 25 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 66708041841 + 28725076338084 = 258279^2 + 5359578^2 .

It is not a de Polignac number, because 28791784379925 - 2⁸ = 28791784379669 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28791784379927) by changing a digit.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 10777632 + ... + 13181081.

Almost surely, 2^{28791784379925} is an apocalyptic number.

28791784379925 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

28791784379925 is an abundant number, since it is smaller than the sum of its proper divisors (31747333742415).

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

28791784379925 is a wasteful number, since it uses less digits than its factorization.

28791784379925 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23958852 (or 23958837 counting only the distinct ones).

The product of its digits is 3840721920, while the sum is 81.

The spelling of 28791784379925 in words is "twenty-eight trillion, seven hundred ninety-one billion, seven hundred eighty-four million, three hundred seventy-nine thousand, nine hundred twenty-five".