318905 has 4 divisors (see below), whose sum is σ = 382692. Its totient is φ = 255120.

The previous prime is 318889. The next prime is 318907. The reversal of 318905 is 509813.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 509813 = 17 ⋅29989.

It can be written as a sum of positive squares in 2 ways, for example, as 139129 + 179776 = 373^2 + 424^2 .

It is not a de Polignac number, because 318905 - 2⁴ = 318889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (318907) 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, 31886 + ... + 31895.

It is an arithmetic number, because the mean of its divisors is an integer number (95673).

2³¹⁸⁹⁰⁵ is an apocalyptic number.

It is an amenable number.

318905 is a deficient number, since it is larger than the sum of its proper divisors (63787).

318905 is an equidigital number, since it uses as much as digits as its factorization.

318905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63786.

The product of its (nonzero) digits is 1080, while the sum is 26.

The square root of 318905 is about 564.7167431554. The cubic root of 318905 is about 68.3209310561.

The spelling of 318905 in words is "three hundred eighteen thousand, nine hundred five".