28657885725 has 288 divisors, whose sum is σ = 64901917440. Its totient is φ = 12138647040.

The previous prime is 28657885723. The next prime is 28657885727. The reversal of 28657885725 is 52758875682.

It is a happy number.

28657885725 is a `hidden beast` number, since 2 + 8 + 6 + 57 + 8 + 8 + 572 + 5 = 666.

It is an interprime number because it is at equal distance from previous prime (28657885723) and next prime (28657885727).

It is not a de Polignac number, because 28657885725 - 2¹ = 28657885723 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28657885723) by changing a digit.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 90403267 + ... + 90403583.

It is an arithmetic number, because the mean of its divisors is an integer number (225353880).

Almost surely, 2^28657885725 is an apocalyptic number.

28657885725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

28657885725 is an abundant number, since it is smaller than the sum of its proper divisors (36244031715).

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

28657885725 is a wasteful number, since it uses less digits than its factorization.

28657885725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 434 (or 404 counting only the distinct ones).

The product of its digits is 75264000, while the sum is 63.

The spelling of 28657885725 in words is "twenty-eight billion, six hundred fifty-seven million, eight hundred eighty-five thousand, seven hundred twenty-five".