393431389 has 8 divisors (see below), whose sum is σ = 425548760. Its totient is φ = 361578816.

The previous prime is 393431387. The next prime is 393431393. The reversal of 393431389 is 983134393.

It can be written as a sum of positive squares in 4 ways, for example, as 89208025 + 304223364 = 9445^2 + 17442^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 393431389 - 2¹ = 393431387 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (393431387) 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 7 ways as a sum of consecutive naturals, for example, 63102 + ... + 69055.

It is an arithmetic number, because the mean of its divisors is an integer number (53193595).

Almost surely, 2^393431389 is an apocalyptic number.

It is an amenable number.

393431389 is a deficient number, since it is larger than the sum of its proper divisors (32117371).

393431389 is a wasteful number, since it uses less digits than its factorization.

393431389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132399.

The product of its digits is 209952, while the sum is 43.

The square root of 393431389 is about 19835.1049656915. The cubic root of 393431389 is about 732.7508575579.

The spelling of 393431389 in words is "three hundred ninety-three million, four hundred thirty-one thousand, three hundred eighty-nine".