388816491 has 8 divisors (see below), whose sum is σ = 592482304. Its totient is φ = 222180840.

The previous prime is 388816487. The next prime is 388816507. The reversal of 388816491 is 194618883.

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

It is not a de Polignac number, because 388816491 - 2² = 388816487 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 388816491.

It is not an unprimeable number, because it can be changed into a prime (388816471) 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, 9257515 + ... + 9257556.

It is an arithmetic number, because the mean of its divisors is an integer number (74060288).

Almost surely, 2^388816491 is an apocalyptic number.

388816491 is a deficient number, since it is larger than the sum of its proper divisors (203665813).

388816491 is a wasteful number, since it uses less digits than its factorization.

388816491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18515081.

The product of its digits is 331776, while the sum is 48.

The square root of 388816491 is about 19718.4302367100. The cubic root of 388816491 is about 729.8745584169.

The spelling of 388816491 in words is "three hundred eighty-eight million, eight hundred sixteen thousand, four hundred ninety-one".