315666389 has 4 divisors (see below), whose sum is σ = 316840140. Its totient is φ = 314492640.

The previous prime is 315666349. The next prime is 315666409. The reversal of 315666389 is 983666513.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 983666513 = 1913 ⋅514201.

It can be written as a sum of positive squares in 2 ways, for example, as 20857489 + 294808900 = 4567^2 + 17170^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-315666389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (315666349) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 586472 + ... + 587009.

It is an arithmetic number, because the mean of its divisors is an integer number (79210035).

Almost surely, 2^315666389 is an apocalyptic number.

It is an amenable number.

315666389 is a deficient number, since it is larger than the sum of its proper divisors (1173751).

315666389 is a wasteful number, since it uses less digits than its factorization.

315666389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1173750.

The product of its digits is 699840, while the sum is 47.

The square root of 315666389 is about 17767.0028142059. The cubic root of 315666389 is about 680.8886802213. Note that the first 3 decimals are identical.

The spelling of 315666389 in words is "three hundred fifteen million, six hundred sixty-six thousand, three hundred eighty-nine".