128504409 has 16 divisors (see below), whose sum is σ = 187453440. Its totient is φ = 77657360.

The previous prime is 128504407. The next prime is 128504413. The reversal of 128504409 is 904405821.

It is not a de Polignac number, because 128504409 - 2¹ = 128504407 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a self number, because there is not a number n which added to its sum of digits gives 128504409.

It is not an unprimeable number, because it can be changed into a prime (128504407) 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, 6424 + ... + 17270.

It is an arithmetic number, because the mean of its divisors is an integer number (11715840).

Almost surely, 2^128504409 is an apocalyptic number.

It is an amenable number.

128504409 is a deficient number, since it is larger than the sum of its proper divisors (58949031).

128504409 is a wasteful number, since it uses less digits than its factorization.

128504409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11220.

The product of its (nonzero) digits is 11520, while the sum is 33.

The square root of 128504409 is about 11335.9785197397. The cubic root of 128504409 is about 504.6295476128.

The spelling of 128504409 in words is "one hundred twenty-eight million, five hundred four thousand, four hundred nine".