128779904 has 32 divisors (see below), whose sum is σ = 279879840. Its totient is φ = 58535680.

The previous prime is 128779901. The next prime is 128779907. The reversal of 128779904 is 409977821.

It is an interprime number because it is at equal distance from previous prime (128779901) and next prime (128779907).

It is a tau number, because it is divible by the number of its divisors (32).

It is not an unprimeable number, because it can be changed into a prime (128779901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 44324 + ... + 47139.

It is an arithmetic number, because the mean of its divisors is an integer number (8746245).

Almost surely, 2^128779904 is an apocalyptic number.

It is an amenable number.

128779904 is an abundant number, since it is smaller than the sum of its proper divisors (151099936).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

128779904 is an equidigital number, since it uses as much as digits as its factorization.

128779904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91488 (or 91476 counting only the distinct ones).

The product of its (nonzero) digits is 254016, while the sum is 47.

The square root of 128779904 is about 11348.1233690862. The cubic root of 128779904 is about 504.9899079773.

The spelling of 128779904 in words is "one hundred twenty-eight million, seven hundred seventy-nine thousand, nine hundred four".