388946989 has 6 divisors (see below), whose sum is σ = 392723210. Its totient is φ = 385174656.

The previous prime is 388946983. The next prime is 388947001. The reversal of 388946989 is 989649883.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 81540900 + 307406089 = 9030^2 + 17533^2 .

It is not a de Polignac number, because 388946989 - 2¹⁵ = 388914221 is a prime.

It is a super-2 number, since 2×388946989² = 302559520504332242, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 388946989.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (388946983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 204957 + ... + 206845.

Almost surely, 2^388946989 is an apocalyptic number.

It is an amenable number.

388946989 is a deficient number, since it is larger than the sum of its proper divisors (3776221).

388946989 is an frugal number, since it uses more digits than its factorization.

388946989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3887 (or 1998 counting only the distinct ones).

The product of its digits is 26873856, while the sum is 64.

The square root of 388946989 is about 19721.7389953320. The cubic root of 388946989 is about 729.9562049163.

The spelling of 388946989 in words is "three hundred eighty-eight million, nine hundred forty-six thousand, nine hundred eighty-nine".