312971891 has 8 divisors (see below), whose sum is σ = 314954640. Its totient is φ = 310995072.

The previous prime is 312971801. The next prime is 312971903. The reversal of 312971891 is 198179213.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-312971891 is a prime.

It is a super-2 number, since 2×312971891² = 195902809112231762, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (312971801) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 148775 + ... + 150863.

It is an arithmetic number, because the mean of its divisors is an integer number (39369330).

Almost surely, 2^312971891 is an apocalyptic number.

312971891 is a deficient number, since it is larger than the sum of its proper divisors (1982749).

312971891 is a wasteful number, since it uses less digits than its factorization.

312971891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2965.

The product of its digits is 27216, while the sum is 41.

The square root of 312971891 is about 17691.0115878092. The cubic root of 312971891 is about 678.9458081588.

The spelling of 312971891 in words is "three hundred twelve million, nine hundred seventy-one thousand, eight hundred ninety-one".