315218 has 6 divisors (see below), whose sum is σ = 474021. Its totient is φ = 157212.

The previous prime is 315199. The next prime is 315223. The reversal of 315218 is 812513.

It can be written as a sum of positive squares in 2 ways, for example, as 305809 + 9409 = 553^2 + 97^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=397.

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 315218.

It is an unprimeable number.

315218 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 596 + ... + 992.

2³¹⁵²¹⁸ is an apocalyptic number.

315218 is a deficient number, since it is larger than the sum of its proper divisors (158803).

315218 is an frugal number, since it uses more digits than its factorization.

315218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 796 (or 399 counting only the distinct ones).

The product of its digits is 240, while the sum is 20.

The square root of 315218 is about 561.4427842621. The cubic root of 315218 is about 68.0566137525.

It can be divided in two parts, 3 and 15218, that multiplied together give a palindrome (45654).

The spelling of 315218 in words is "three hundred fifteen thousand, two hundred eighteen".