388888831 has 6 divisors (see below), whose sum is σ = 401839296. Its totient is φ = 376343100.

The previous prime is 388888771. The next prime is 388888867. The reversal of 388888831 is 138888883.

It is not a de Polignac number, because 388888831 - 2⁹ = 388888319 is a prime.

It is a super-2 number, since 2×388888831² = 302469045753093122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (388888891) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 201375 + ... + 203296.

It is an arithmetic number, because the mean of its divisors is an integer number (66973216).

Almost surely, 2^388888831 is an apocalyptic number.

388888831 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

388888831 is the 11386-th hex number.

388888831 is a deficient number, since it is larger than the sum of its proper divisors (12950465).

388888831 is an equidigital number, since it uses as much as digits as its factorization.

388888831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 404733 (or 404702 counting only the distinct ones).

The product of its digits is 2359296, while the sum is 55.

The square root of 388888831 is about 19720.2644759141. The cubic root of 388888831 is about 729.9198204301.

The spelling of 388888831 in words is "three hundred eighty-eight million, eight hundred eighty-eight thousand, eight hundred thirty-one".