318161813 has 16 divisors (see below), whose sum is σ = 336383280. Its totient is φ = 300496896.

The previous prime is 318161791. The next prime is 318161861.

318161813 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 8 ways, for example, as 145924 + 318015889 = 382^2 + 17833^2 .

It is not a de Polignac number, because 318161813 - 2²⁸ = 49726357 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 318161813.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (318161513) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 289481 + ... + 290577.

It is an arithmetic number, because the mean of its divisors is an integer number (21023955).

Almost surely, 2^318161813 is an apocalyptic number.

It is an amenable number.

318161813 is a deficient number, since it is larger than the sum of its proper divisors (18221467).

318161813 is a wasteful number, since it uses less digits than its factorization.

318161813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1336.

The product of its digits is 3456, while the sum is 32.

The square root of 318161813 is about 17837.0909343424. The cubic root of 318161813 is about 682.6781730567.

The spelling of 318161813 in words is "three hundred eighteen million, one hundred sixty-one thousand, eight hundred thirteen".