312381 has 12 divisors (see below), whose sum is σ = 459420. Its totient is φ = 204480.

The previous prime is 312371. The next prime is 312383. The reversal of 312381 is 183213.

It can be written as a sum of positive squares in 2 ways, for example, as 27225 + 285156 = 165^2 + 534^2 .

It is not a de Polignac number, because 312381 - 2⁵ = 312349 is a prime.

It is a super-2 number, since 2×312381² = 195163778322, which contains 22 as substring.

It is a Curzon 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 312381.

It is not an unprimeable number, because it can be changed into a prime (312383) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 265 + ... + 833.

It is an arithmetic number, because the mean of its divisors is an integer number (38285).

2³¹²³⁸¹ is an apocalyptic number.

It is an amenable number.

312381 is a deficient number, since it is larger than the sum of its proper divisors (147039).

312381 is a wasteful number, since it uses less digits than its factorization.

312381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 636 (or 633 counting only the distinct ones).

The product of its digits is 144, while the sum is 18.

The square root of 312381 is about 558.9105474045. The cubic root of 312381 is about 67.8518255694.

Adding to 312381 its reverse (183213), we get a palindrome (495594).

The spelling of 312381 in words is "three hundred twelve thousand, three hundred eighty-one".