312161665 has 4 divisors (see below), whose sum is σ = 374594004. Its totient is φ = 249729328.

The previous prime is 312161657. The next prime is 312161677. The reversal of 312161665 is 566161213.

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

It can be written as a sum of positive squares in 2 ways, for example, as 50013184 + 262148481 = 7072^2 + 16191^2 .

It is a cyclic number.

It is not a de Polignac number, because 312161665 - 2³ = 312161657 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

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, 31216162 + ... + 31216171.

It is an arithmetic number, because the mean of its divisors is an integer number (93648501).

Almost surely, 2^312161665 is an apocalyptic number.

It is an amenable number.

312161665 is a deficient number, since it is larger than the sum of its proper divisors (62432339).

312161665 is an equidigital number, since it uses as much as digits as its factorization.

312161665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62432338.

The product of its digits is 6480, while the sum is 31.

The square root of 312161665 is about 17668.0973791747. The cubic root of 312161665 is about 678.3594137169.

The spelling of 312161665 in words is "three hundred twelve million, one hundred sixty-one thousand, six hundred sixty-five".