128927929 has 16 divisors (see below), whose sum is σ = 140904400. Its totient is φ = 117262080.

The previous prime is 128927923. The next prime is 128927951. The reversal of 128927929 is 929729821.

It can be written as a sum of positive squares in 8 ways, for example, as 31866025 + 97061904 = 5645^2 + 9852^2 .

It is not a de Polignac number, because 128927929 - 2²¹ = 126830777 is a prime.

It is not an unprimeable number, because it can be changed into a prime (128927923) 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, 369247 + ... + 369595.

It is an arithmetic number, because the mean of its divisors is an integer number (8806525).

Almost surely, 2^128927929 is an apocalyptic number.

It is an amenable number.

128927929 is a deficient number, since it is larger than the sum of its proper divisors (11976471).

128927929 is a wasteful number, since it uses less digits than its factorization.

128927929 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 700.

The product of its digits is 326592, while the sum is 49.

The square root of 128927929 is about 11354.6434994675. The cubic root of 128927929 is about 505.1833193880.

The spelling of 128927929 in words is "one hundred twenty-eight million, nine hundred twenty-seven thousand, nine hundred twenty-nine".