128798785 has 8 divisors (see below), whose sum is σ = 154659240. Its totient is φ = 102971904.

The previous prime is 128798771. The next prime is 128798801. The reversal of 128798785 is 587897821.

It can be written as a sum of positive squares in 4 ways, for example, as 2663424 + 126135361 = 1632^2 + 11231^2 .

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 128798785 - 2²³ = 120410177 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1009 + ... + 16081.

It is an arithmetic number, because the mean of its divisors is an integer number (19332405).

Almost surely, 2^128798785 is an apocalyptic number.

It is an amenable number.

128798785 is a deficient number, since it is larger than the sum of its proper divisors (25860455).

128798785 is a wasteful number, since it uses less digits than its factorization.

128798785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16787.

The product of its digits is 2257920, while the sum is 55.

The square root of 128798785 is about 11348.9552382587. The cubic root of 128798785 is about 505.0145863839.

The spelling of 128798785 in words is "one hundred twenty-eight million, seven hundred ninety-eight thousand, seven hundred eighty-five".