128838811 has 4 divisors (see below), whose sum is σ = 129121192. Its totient is φ = 128556432.

The previous prime is 128838799. The next prime is 128838823. The reversal of 128838811 is 118838821.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (128838799) and next prime (128838823).

It is a cyclic number.

It is not a de Polignac number, because 128838811 - 2⁵ = 128838779 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128838881) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 140505 + ... + 141418.

It is an arithmetic number, because the mean of its divisors is an integer number (32280298).

Almost surely, 2^128838811 is an apocalyptic number.

128838811 is a deficient number, since it is larger than the sum of its proper divisors (282381).

128838811 is an equidigital number, since it uses as much as digits as its factorization.

128838811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 282380.

The product of its digits is 24576, while the sum is 40.

The square root of 128838811 is about 11350.7185235121. The cubic root of 128838811 is about 505.0668943833.

The spelling of 128838811 in words is "one hundred twenty-eight million, eight hundred thirty-eight thousand, eight hundred eleven".