128709688 has 32 divisors (see below), whose sum is σ = 249076800. Its totient is φ = 62318592.

The previous prime is 128709673. The next prime is 128709689. The reversal of 128709688 is 886907821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128709689) 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, 34708 + ... + 38236.

It is an arithmetic number, because the mean of its divisors is an integer number (7783650).

Almost surely, 2^128709688 is an apocalyptic number.

It is an amenable number.

128709688 is a deficient number, since it is larger than the sum of its proper divisors (120367112).

128709688 is a wasteful number, since it uses less digits than its factorization.

128709688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3679 (or 3675 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 49.

The square root of 128709688 is about 11345.0292198830. The cubic root of 128709688 is about 504.8981109999.

The spelling of 128709688 in words is "one hundred twenty-eight million, seven hundred nine thousand, six hundred eighty-eight".