388816489 has 8 divisors (see below), whose sum is σ = 399205800. Its totient is φ = 378470400.

The previous prime is 388816487. The next prime is 388816507. The reversal of 388816489 is 984618883.

It can be written as a sum of positive squares in 4 ways, for example, as 31304025 + 357512464 = 5595^2 + 18908^2 .

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 388816489 - 2¹ = 388816487 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (388816481) 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 7 ways as a sum of consecutive naturals, for example, 7849 + ... + 28969.

It is an arithmetic number, because the mean of its divisors is an integer number (49900725).

Almost surely, 2^388816489 is an apocalyptic number.

It is an amenable number.

388816489 is a deficient number, since it is larger than the sum of its proper divisors (10389311).

388816489 is a wasteful number, since it uses less digits than its factorization.

388816489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21611.

The product of its digits is 2654208, while the sum is 55.

The square root of 388816489 is about 19718.4301859960. The cubic root of 388816489 is about 729.8745571654.

The spelling of 388816489 in words is "three hundred eighty-eight million, eight hundred sixteen thousand, four hundred eighty-nine".