128689437 has 8 divisors (see below), whose sum is σ = 173936704. Its totient is φ = 84617568.

The previous prime is 128689403. The next prime is 128689471. The reversal of 128689437 is 734986821.

It is an interprime number because it is at equal distance from previous prime (128689403) and next prime (128689471).

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

It is not a de Polignac number, because 128689437 - 2⁶ = 128689373 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128689537) 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, 293593 + ... + 294030.

It is an arithmetic number, because the mean of its divisors is an integer number (21742088).

Almost surely, 2^128689437 is an apocalyptic number.

It is an amenable number.

128689437 is a deficient number, since it is larger than the sum of its proper divisors (45247267).

128689437 is an equidigital number, since it uses as much as digits as its factorization.

128689437 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 587699.

The product of its digits is 580608, while the sum is 48.

The square root of 128689437 is about 11344.1366793600. The cubic root of 128689437 is about 504.8716296265.

The spelling of 128689437 in words is "one hundred twenty-eight million, six hundred eighty-nine thousand, four hundred thirty-seven".