388809 has 6 divisors (see below), whose sum is σ = 561626. Its totient is φ = 259200.

The previous prime is 388793. The next prime is 388813. The reversal of 388809 is 908883.

It can be written as a sum of positive squares in only one way, i.e., 356409 + 32400 = 597^2 + 180^2 .

It is not a de Polignac number, because 388809 - 2⁴ = 388793 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (388859) 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, 21592 + ... + 21609.

2³⁸⁸⁸⁰⁹ is an apocalyptic number.

It is an amenable number.

388809 is a deficient number, since it is larger than the sum of its proper divisors (172817).

388809 is a wasteful number, since it uses less digits than its factorization.

388809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43207 (or 43204 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 388809 is about 623.5455075614. The cubic root of 388809 is about 72.9869871094.

The spelling of 388809 in words is "three hundred eighty-eight thousand, eight hundred nine".