128937639 has 24 divisors (see below), whose sum is σ = 184219648. Its totient is φ = 80196480.

The previous prime is 128937631. The next prime is 128937643. The reversal of 128937639 is 936739821.

It is not a de Polignac number, because 128937639 - 2³ = 128937631 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 (128937631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 109524 + ... + 110694.

Almost surely, 2^128937639 is an apocalyptic number.

128937639 is a deficient number, since it is larger than the sum of its proper divisors (55282009).

128937639 is a wasteful number, since it uses less digits than its factorization.

128937639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1335 (or 1318 counting only the distinct ones).

The product of its digits is 489888, while the sum is 48.

The square root of 128937639 is about 11355.0710697908. The cubic root of 128937639 is about 505.1960014265.

The spelling of 128937639 in words is "one hundred twenty-eight million, nine hundred thirty-seven thousand, six hundred thirty-nine".