128857389 has 8 divisors (see below), whose sum is σ = 171976032. Its totient is φ = 85821840.

The previous prime is 128857381. The next prime is 128857397. The reversal of 128857389 is 983758821.

It is an interprime number because it is at equal distance from previous prime (128857381) and next prime (128857397).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 128857389 - 2³ = 128857381 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128857381) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17059 + ... + 23424.

It is an arithmetic number, because the mean of its divisors is an integer number (21497004).

Almost surely, 2^128857389 is an apocalyptic number.

It is an amenable number.

128857389 is a deficient number, since it is larger than the sum of its proper divisors (43118643).

128857389 is a wasteful number, since it uses less digits than its factorization.

128857389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41547.

The product of its digits is 967680, while the sum is 51.

The square root of 128857389 is about 11351.5368563028. The cubic root of 128857389 is about 505.0911693713.

The spelling of 128857389 in words is "one hundred twenty-eight million, eight hundred fifty-seven thousand, three hundred eighty-nine".