128436789 has 48 divisors (see below), whose sum is σ = 199104000. Its totient is φ = 73389888.

The previous prime is 128436787. The next prime is 128436809. The reversal of 128436789 is 987634821.

It is not a de Polignac number, because 128436789 - 2¹ = 128436787 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128436787) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 645312 + ... + 645510.

It is an arithmetic number, because the mean of its divisors is an integer number (4148000).

Almost surely, 2^128436789 is an apocalyptic number.

128436789 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

128436789 is a deficient number, since it is larger than the sum of its proper divisors (70667211).

128436789 is a wasteful number, since it uses less digits than its factorization.

128436789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 314 (or 301 counting only the distinct ones).

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

The square root of 128436789 is about 11332.9955881047. The cubic root of 128436789 is about 504.5410187774.

The spelling of 128436789 in words is "one hundred twenty-eight million, four hundred thirty-six thousand, seven hundred eighty-nine".