128444409 has 12 divisors (see below), whose sum is σ = 187767216. Its totient is φ = 84597432.

The previous prime is 128444383. The next prime is 128444411. The reversal of 128444409 is 904444821.

It is not a de Polignac number, because 128444409 - 2²³ = 120055801 is a prime.

It is not an unprimeable number, because it can be changed into a prime (128444419) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 85227 + ... + 86720.

It is an arithmetic number, because the mean of its divisors is an integer number (15647268).

Almost surely, 2^128444409 is an apocalyptic number.

It is an amenable number.

128444409 is a deficient number, since it is larger than the sum of its proper divisors (59322807).

128444409 is a wasteful number, since it uses less digits than its factorization.

128444409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172036 (or 172033 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 36.

The square root of 128444409 is about 11333.3317696077. The cubic root of 128444409 is about 504.5509965170.

The spelling of 128444409 in words is "one hundred twenty-eight million, four hundred forty-four thousand, four hundred nine".