317981 has 4 divisors (see below), whose sum is σ = 319200. Its totient is φ = 316764.

The previous prime is 317971. The next prime is 317983. The reversal of 317981 is 189713.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 317981 - 2¹⁰ = 316957 is a prime.

It is a super-2 number, since 2×317981² = 202223832722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 317981.

It is not an unprimeable number, because it can be changed into a prime (317983) 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, 41 + ... + 798.

It is an arithmetic number, because the mean of its divisors is an integer number (79800).

2³¹⁷⁹⁸¹ is an apocalyptic number.

It is an amenable number.

317981 is a deficient number, since it is larger than the sum of its proper divisors (1219).

317981 is an equidigital number, since it uses as much as digits as its factorization.

317981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1218.

The product of its digits is 1512, while the sum is 29.

The square root of 317981 is about 563.8980404293. The cubic root of 317981 is about 68.2548825375.

The spelling of 317981 in words is "three hundred seventeen thousand, nine hundred eighty-one".