388256978 has 6 divisors (see below), whose sum is σ = 582427269. Its totient is φ = 194114556.

The previous prime is 388256977. The next prime is 388256983. The reversal of 388256978 is 879652883.

It can be written as a sum of positive squares in 2 ways, for example, as 213832129 + 174424849 = 14623^2 + 13207^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=13933.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (388256971) 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 2 ways as a sum of consecutive naturals, for example, 20900 + ... + 34832.

Almost surely, 2^388256978 is an apocalyptic number.

388256978 is a deficient number, since it is larger than the sum of its proper divisors (194170291).

388256978 is an frugal number, since it uses more digits than its factorization.

388256978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27868 (or 13935 counting only the distinct ones).

The product of its digits is 5806080, while the sum is 56.

The square root of 388256978 is about 19704.2375645443. The cubic root of 388256978 is about 729.5242900549.

The spelling of 388256978 in words is "three hundred eighty-eight million, two hundred fifty-six thousand, nine hundred seventy-eight".