388379991 has 8 divisors (see below), whose sum is σ = 524079360. Its totient is φ = 255800312.

The previous prime is 388379989. The next prime is 388380017. The reversal of 388379991 is 199973883.

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 388379991 - 2¹ = 388379989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (388379911) 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, 779631 + ... + 780128.

It is an arithmetic number, because the mean of its divisors is an integer number (65509920).

Almost surely, 2^388379991 is an apocalyptic number.

388379991 is a deficient number, since it is larger than the sum of its proper divisors (135699369).

388379991 is a wasteful number, since it uses less digits than its factorization.

388379991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1559845.

The product of its digits is 2939328, while the sum is 57.

The square root of 388379991 is about 19707.3588032491. The cubic root of 388379991 is about 729.6013279452.

It can be divided in two parts, 38837 and 9991, that added together give a triangular number (48828 = T₃₁₂).

The spelling of 388379991 in words is "three hundred eighty-eight million, three hundred seventy-nine thousand, nine hundred ninety-one".