128494409 has 8 divisors (see below), whose sum is σ = 131447808. Its totient is φ = 125571600.

The previous prime is 128494403. The next prime is 128494423. The reversal of 128494409 is 904494821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 128494409 - 2²⁰ = 127445833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128494403) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 959 + ... + 16059.

It is an arithmetic number, because the mean of its divisors is an integer number (16430976).

Almost surely, 2^128494409 is an apocalyptic number.

It is an amenable number.

128494409 is a deficient number, since it is larger than the sum of its proper divisors (2953399).

128494409 is a wasteful number, since it uses less digits than its factorization.

128494409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15295.

The product of its (nonzero) digits is 82944, while the sum is 41.

The square root of 128494409 is about 11335.5374376339. The cubic root of 128494409 is about 504.6164574617.

The spelling of 128494409 in words is "one hundred twenty-eight million, four hundred ninety-four thousand, four hundred nine".