388405391 has 16 divisors (see below), whose sum is σ = 458079360. Its totient is φ = 325464480.

The previous prime is 388405379. The next prime is 388405447. The reversal of 388405391 is 193504883.

It is not a de Polignac number, because 388405391 - 2⁶ = 388405327 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (388405891) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17381 + ... + 32846.

It is an arithmetic number, because the mean of its divisors is an integer number (28629960).

Almost surely, 2^388405391 is an apocalyptic number.

388405391 is a deficient number, since it is larger than the sum of its proper divisors (69673969).

388405391 is a wasteful number, since it uses less digits than its factorization.

388405391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50294.

The product of its (nonzero) digits is 103680, while the sum is 41.

The square root of 388405391 is about 19708.0032220415. The cubic root of 388405391 is about 729.6172328753.

The spelling of 388405391 in words is "three hundred eighty-eight million, four hundred five thousand, three hundred ninety-one".