388531 has 18 divisors (see below), whose sum is σ = 486780. Its totient is φ = 308880.

The previous prime is 388529. The next prime is 388541. The reversal of 388531 is 135883.

It is not a de Polignac number, because 388531 - 2¹ = 388529 is a prime.

It is a super-2 number, since 2×388531² = 301912675922, which contains 22 as substring.

388531 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 388531.

It is not an unprimeable number, because it can be changed into a prime (388541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 20440 + ... + 20458.

2³⁸⁸⁵³¹ is an apocalyptic number.

388531 is a deficient number, since it is larger than the sum of its proper divisors (98249).

388531 is a wasteful number, since it uses less digits than its factorization.

388531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67 (or 43 counting only the distinct ones).

The product of its digits is 2880, while the sum is 28.

The square root of 388531 is about 623.3225489263. The cubic root of 388531 is about 72.9695876320.

It can be divided in two parts, 3885 and 31, that added together give a triangular number (3916 = T₈₈).

The spelling of 388531 in words is "three hundred eighty-eight thousand, five hundred thirty-one".