388668021 has 8 divisors (see below), whose sum is σ = 592256064. Its totient is φ = 222096000.

The previous prime is 388668011. The next prime is 388668037. The reversal of 388668021 is 120866883.

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

It is not a de Polignac number, because 388668021 - 2⁷ = 388667893 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (388668011) 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, 9253980 + ... + 9254021.

It is an arithmetic number, because the mean of its divisors is an integer number (74032008).

Almost surely, 2^388668021 is an apocalyptic number.

It is an amenable number.

388668021 is a deficient number, since it is larger than the sum of its proper divisors (203588043).

388668021 is a wasteful number, since it uses less digits than its factorization.

388668021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18508011.

The product of its (nonzero) digits is 110592, while the sum is 42.

The square root of 388668021 is about 19714.6651252310. The cubic root of 388668021 is about 729.7816454582.

The spelling of 388668021 in words is "three hundred eighty-eight million, six hundred sixty-eight thousand, twenty-one".