166315321 has 4 divisors (see below), whose sum is σ = 167787252. Its totient is φ = 164843392.

The previous prime is 166315309. The next prime is 166315337. The reversal of 166315321 is 123513661.

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 73770921 + 92544400 = 8589^2 + 9620^2 .

It is a cyclic number.

It is not a de Polignac number, because 166315321 - 2¹³ = 166307129 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 166315321.

It is not an unprimeable number, because it can be changed into a prime (166325321) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 735796 + ... + 736021.

It is an arithmetic number, because the mean of its divisors is an integer number (41946813).

Almost surely, 2^166315321 is an apocalyptic number.

It is an amenable number.

166315321 is a deficient number, since it is larger than the sum of its proper divisors (1471931).

166315321 is a wasteful number, since it uses less digits than its factorization.

166315321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1471930.

The product of its digits is 3240, while the sum is 28.

The square root of 166315321 is about 12896.3297491961. The cubic root of 166315321 is about 549.9342301520.

Adding to 166315321 its reverse (123513661), we get a palindrome (289828982).

It can be divided in two parts, 16631 and 5321, that added together give a cube (21952 = 28³).

The spelling of 166315321 in words is "one hundred sixty-six million, three hundred fifteen thousand, three hundred twenty-one".