128778698 has 8 divisors (see below), whose sum is σ = 193267620. Its totient is φ = 64356160.

The previous prime is 128778691. The next prime is 128778701. The reversal of 128778698 is 896877821.

It can be written as a sum of positive squares in 2 ways, for example, as 124925329 + 3853369 = 11177^2 + 1963^2 .

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

It is not an unprimeable number, because it can be changed into a prime (128778691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11423 + ... + 19698.

Almost surely, 2^128778698 is an apocalyptic number.

128778698 is a deficient number, since it is larger than the sum of its proper divisors (64488922).

128778698 is a wasteful number, since it uses less digits than its factorization.

128778698 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33192.

The product of its digits is 2709504, while the sum is 56.

The square root of 128778698 is about 11348.0702324228. The cubic root of 128778698 is about 504.9883315933.

The spelling of 128778698 in words is "one hundred twenty-eight million, seven hundred seventy-eight thousand, six hundred ninety-eight".