388721 has 8 divisors (see below), whose sum is σ = 420000. Its totient is φ = 358560.

The previous prime is 388711. The next prime is 388727. The reversal of 388721 is 127883.

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 388721 - 2⁶ = 388657 is a prime.

It is a super-2 number, since 2×388721² = 302208031682, which contains 22 as substring.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 388721.

It is not an unprimeable number, because it can be changed into a prime (388727) 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, 530 + ... + 1028.

It is an arithmetic number, because the mean of its divisors is an integer number (52500).

2³⁸⁸⁷²¹ is an apocalyptic number.

It is an amenable number.

388721 is a deficient number, since it is larger than the sum of its proper divisors (31279).

388721 is a wasteful number, since it uses less digits than its factorization.

388721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 559.

The product of its digits is 2688, while the sum is 29.

The square root of 388721 is about 623.4749393520. The cubic root of 388721 is about 72.9814802586.

The spelling of 388721 in words is "three hundred eighty-eight thousand, seven hundred twenty-one".