128389656 has 32 divisors (see below), whose sum is σ = 321251760. Its totient is φ = 42759552.

The previous prime is 128389649. The next prime is 128389697. The reversal of 128389656 is 656983821.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 53866 + ... + 56198.

Almost surely, 2^128389656 is an apocalyptic number.

It is an amenable number.

128389656 is an abundant number, since it is smaller than the sum of its proper divisors (192862104).

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

128389656 is a wasteful number, since it uses less digits than its factorization.

128389656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4635 (or 4631 counting only the distinct ones).

The product of its digits is 622080, while the sum is 48.

The square root of 128389656 is about 11330.9159382638. The cubic root of 128389656 is about 504.4792933648.

The spelling of 128389656 in words is "one hundred twenty-eight million, three hundred eighty-nine thousand, six hundred fifty-six".