128938777 has 8 divisors (see below), whose sum is σ = 143045280. Its totient is φ = 115229760.

The previous prime is 128938751. The next prime is 128938781. The reversal of 128938777 is 777839821.

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 128938777 - 2²³ = 120550169 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128938787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 98688 + ... + 99985.

It is an arithmetic number, because the mean of its divisors is an integer number (17880660).

Almost surely, 2^128938777 is an apocalyptic number.

It is an amenable number.

128938777 is a deficient number, since it is larger than the sum of its proper divisors (14106503).

128938777 is a wasteful number, since it uses less digits than its factorization.

128938777 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198743.

The product of its digits is 1185408, while the sum is 52.

The square root of 128938777 is about 11355.1211794503. The cubic root of 128938777 is about 505.1974877041.

The spelling of 128938777 in words is "one hundred twenty-eight million, nine hundred thirty-eight thousand, seven hundred seventy-seven".