128865525 has 48 divisors (see below), whose sum is σ = 229967424. Its totient is φ = 63431680.

The previous prime is 128865469. The next prime is 128865533. The reversal of 128865525 is 525568821.

It is not a de Polignac number, because 128865525 - 2⁶ = 128865461 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 66622 + ... + 68528.

It is an arithmetic number, because the mean of its divisors is an integer number (4790988).

Almost surely, 2^128865525 is an apocalyptic number.

128865525 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

128865525 is a deficient number, since it is larger than the sum of its proper divisors (101101899).

128865525 is a wasteful number, since it uses less digits than its factorization.

128865525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1990 (or 1985 counting only the distinct ones).

The product of its digits is 192000, while the sum is 42.

The square root of 128865525 is about 11351.8952162183. The cubic root of 128865525 is about 505.1017995605.

The spelling of 128865525 in words is "one hundred twenty-eight million, eight hundred sixty-five thousand, five hundred twenty-five".