389817621 has 12 divisors (see below), whose sum is σ = 565489548. Its totient is φ = 258761664.

The previous prime is 389817601. The next prime is 389817629. The reversal of 389817621 is 126718983.

389817621 is a `hidden beast` number, since 3 + 8 + 9 + 8 + 17 + 621 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 103734225 + 286083396 = 10185^2 + 16914^2 .

It is not a de Polignac number, because 389817621 - 2²¹ = 387720469 is a prime.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (389817629) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 90850 + ... + 95043.

It is an arithmetic number, because the mean of its divisors is an integer number (47124129).

Almost surely, 2^389817621 is an apocalyptic number.

It is an amenable number.

389817621 is a deficient number, since it is larger than the sum of its proper divisors (175671927).

389817621 is a wasteful number, since it uses less digits than its factorization.

389817621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 186132 (or 186129 counting only the distinct ones).

The product of its digits is 145152, while the sum is 45.

The square root of 389817621 is about 19743.7995583424. The cubic root of 389817621 is about 730.5004518575.

The spelling of 389817621 in words is "three hundred eighty-nine million, eight hundred seventeen thousand, six hundred twenty-one".