128736939 has 8 divisors (see below), whose sum is σ = 172521360. Its totient is φ = 85388576.

The previous prime is 128736931. The next prime is 128736967. The reversal of 128736939 is 939637821.

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

It is a cyclic number.

It is not a de Polignac number, because 128736939 - 2³ = 128736931 is a prime.

It is not an unprimeable number, because it can be changed into a prime (128736931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 108324 + ... + 109505.

It is an arithmetic number, because the mean of its divisors is an integer number (21565170).

Almost surely, 2^128736939 is an apocalyptic number.

128736939 is a deficient number, since it is larger than the sum of its proper divisors (43784421).

128736939 is a wasteful number, since it uses less digits than its factorization.

128736939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218029.

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

The square root of 128736939 is about 11346.2301668880. The cubic root of 128736939 is about 504.9337415929.

It can be divided in two parts, 1287 and 36939, that added together give a triangular number (38226 = T₂₇₆).

The spelling of 128736939 in words is "one hundred twenty-eight million, seven hundred thirty-six thousand, nine hundred thirty-nine".