128777428 has 12 divisors (see below), whose sum is σ = 242696020. Its totient is φ = 59435712.

The previous prime is 128777423. The next prime is 128777443. The reversal of 128777428 is 824777821.

It can be written as a sum of positive squares in 2 ways, for example, as 18905104 + 109872324 = 4348^2 + 10482^2 .

It is a hoax number, since the sum of its digits (46) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128777423) 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 3 ways as a sum of consecutive naturals, for example, 1238193 + ... + 1238296.

Almost surely, 2^128777428 is an apocalyptic number.

It is an amenable number.

128777428 is a deficient number, since it is larger than the sum of its proper divisors (113918592).

128777428 is a wasteful number, since it uses less digits than its factorization.

128777428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2476506 (or 2476504 counting only the distinct ones).

The product of its digits is 351232, while the sum is 46.

The square root of 128777428 is about 11348.0142756343. The cubic root of 128777428 is about 504.9866715431.

The spelling of 128777428 in words is "one hundred twenty-eight million, seven hundred seventy-seven thousand, four hundred twenty-eight".