128434749 has 16 divisors (see below), whose sum is σ = 173107200. Its totient is φ = 84697776.

The previous prime is 128434729. The next prime is 128434751. The reversal of 128434749 is 947434821.

It is not a de Polignac number, because 128434749 - 2²⁰ = 127386173 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 128434749.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128434729) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 199422 + ... + 200064.

It is an arithmetic number, because the mean of its divisors is an integer number (10819200).

Almost surely, 2^128434749 is an apocalyptic number.

It is an amenable number.

128434749 is a deficient number, since it is larger than the sum of its proper divisors (44672451).

128434749 is a wasteful number, since it uses less digits than its factorization.

128434749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1264.

The product of its digits is 193536, while the sum is 42.

The square root of 128434749 is about 11332.9055850651. The cubic root of 128434749 is about 504.5383475045.

The spelling of 128434749 in words is "one hundred twenty-eight million, four hundred thirty-four thousand, seven hundred forty-nine".