128715657 has 16 divisors (see below), whose sum is σ = 200312832. Its totient is φ = 71986320.

The previous prime is 128715649. The next prime is 128715661. The reversal of 128715657 is 756517821.

It is not a de Polignac number, because 128715657 - 2³ = 128715649 is a prime.

It is not an unprimeable number, because it can be changed into a prime (128715607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 64219 + ... + 66192.

It is an arithmetic number, because the mean of its divisors is an integer number (12519552).

Almost surely, 2^128715657 is an apocalyptic number.

It is an amenable number.

128715657 is a deficient number, since it is larger than the sum of its proper divisors (71597175).

128715657 is a wasteful number, since it uses less digits than its factorization.

128715657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130468.

The product of its digits is 117600, while the sum is 42.

The square root of 128715657 is about 11345.2922835862. The cubic root of 128715657 is about 504.9059158779.

It can be divided in two parts, 12871 and 5657, that added together give a triangular number (18528 = T₁₉₂).

The spelling of 128715657 in words is "one hundred twenty-eight million, seven hundred fifteen thousand, six hundred fifty-seven".