775128389 has 8 divisors (see below), whose sum is σ = 932485440. Its totient is φ = 629427456.

The previous prime is 775128373. The next prime is 775128391. The reversal of 775128389 is 983821577.

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

It is not a de Polignac number, because 775128389 - 2⁴ = 775128373 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (775128349) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2913884 + ... + 2914149.

It is an arithmetic number, because the mean of its divisors is an integer number (116560680).

Almost surely, 2^775128389 is an apocalyptic number.

It is an amenable number.

775128389 is a deficient number, since it is larger than the sum of its proper divisors (157357051).

775128389 is a wasteful number, since it uses less digits than its factorization.

775128389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5828059.

The product of its digits is 846720, while the sum is 50.

The square root of 775128389 is about 27841.1276531681. The cubic root of 775128389 is about 918.5959952642.

The spelling of 775128389 in words is "seven hundred seventy-five million, one hundred twenty-eight thousand, three hundred eighty-nine".