128855815 has 16 divisors (see below), whose sum is σ = 177563520. Its totient is φ = 88780320.

The previous prime is 128855813. The next prime is 128855849. The reversal of 128855815 is 518558821.

It is not a de Polignac number, because 128855815 - 2¹ = 128855813 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128855813) 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, 60609 + ... + 62698.

It is an arithmetic number, because the mean of its divisors is an integer number (11097720).

Almost surely, 2^128855815 is an apocalyptic number.

128855815 is a deficient number, since it is larger than the sum of its proper divisors (48707705).

128855815 is a wasteful number, since it uses less digits than its factorization.

128855815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123342.

The product of its digits is 128000, while the sum is 43.

The square root of 128855815 is about 11351.4675262717. The cubic root of 128855815 is about 505.0891127910.

The spelling of 128855815 in words is "one hundred twenty-eight million, eight hundred fifty-five thousand, eight hundred fifteen".