312315981 has 4 divisors (see below), whose sum is σ = 416421312. Its totient is φ = 208210652.

The previous prime is 312315967. The next prime is 312315989. The reversal of 312315981 is 189513213.

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.

It is a cyclic number.

It is not a de Polignac number, because 312315981 - 2¹³ = 312307789 is a prime.

It is a super-3 number, since 3×312315981³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (312315989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 52052661 + ... + 52052666.

It is an arithmetic number, because the mean of its divisors is an integer number (104105328).

Almost surely, 2^312315981 is an apocalyptic number.

It is an amenable number.

312315981 is a deficient number, since it is larger than the sum of its proper divisors (104105331).

312315981 is a wasteful number, since it uses less digits than its factorization.

312315981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104105330.

The product of its digits is 6480, while the sum is 33.

The square root of 312315981 is about 17672.4639198953. The cubic root of 312315981 is about 678.4711768171.

The spelling of 312315981 in words is "three hundred twelve million, three hundred fifteen thousand, nine hundred eighty-one".