312491291 has 4 divisors (see below), whose sum is σ = 357132912. Its totient is φ = 267849672.

The previous prime is 312491287. The next prime is 312491303. The reversal of 312491291 is 192194213.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 312491291 - 2² = 312491287 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (312491261) 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, 22320800 + ... + 22320813.

It is an arithmetic number, because the mean of its divisors is an integer number (89283228).

Almost surely, 2^312491291 is an apocalyptic number.

312491291 is a deficient number, since it is larger than the sum of its proper divisors (44641621).

312491291 is an equidigital number, since it uses as much as digits as its factorization.

312491291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44641620.

The product of its digits is 3888, while the sum is 32.

The square root of 312491291 is about 17677.4232002292. The cubic root of 312491291 is about 678.5981001267.

The spelling of 312491291 in words is "three hundred twelve million, four hundred ninety-one thousand, two hundred ninety-one".