389909 has 8 divisors (see below), whose sum is σ = 425880. Its totient is φ = 354816.

The previous prime is 389903. The next prime is 389911. The reversal of 389909 is 909983.

389909 = 17² + 18² + ... + 105².

It can be written as a sum of positive squares in 4 ways, for example, as 3025 + 386884 = 55^2 + 622^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-389909 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (389903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 989 + ... + 1325.

It is an arithmetic number, because the mean of its divisors is an integer number (53235).

2³⁸⁹⁹⁰⁹ is an apocalyptic number.

It is an amenable number.

389909 is a deficient number, since it is larger than the sum of its proper divisors (35971).

389909 is a wasteful number, since it uses less digits than its factorization.

389909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 439.

The product of its (nonzero) digits is 17496, while the sum is 38.

The square root of 389909 is about 624.4269372793. The cubic root of 389909 is about 73.0557527425.

The spelling of 389909 in words is "three hundred eighty-nine thousand, nine hundred nine".