317389991 has 4 divisors (see below), whose sum is σ = 317425632. Its totient is φ = 317354352.

The previous prime is 317389967. The next prime is 317389999. The reversal of 317389991 is 199983713.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 199983713 = 11117 ⋅17989.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-317389991 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 (317389999) 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, 8306 + ... + 26528.

It is an arithmetic number, because the mean of its divisors is an integer number (79356408).

Almost surely, 2^317389991 is an apocalyptic number.

317389991 is a deficient number, since it is larger than the sum of its proper divisors (35641).

317389991 is a wasteful number, since it uses less digits than its factorization.

317389991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35640.

The product of its digits is 367416, while the sum is 50.

The square root of 317389991 is about 17815.4424867866. The cubic root of 317389991 is about 682.1256945625.

The spelling of 317389991 in words is "three hundred seventeen million, three hundred eighty-nine thousand, nine hundred ninety-one".