318787813 has 2 divisors, whose sum is σ = 318787814. Its totient is φ = 318787812.

The previous prime is 318787789. The next prime is 318787817.

It is a happy number.

318787813 is nontrivially palindromic in base 10.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 233539524 + 85248289 = 15282^2 + 9233^2 .

It is a palprime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-318787813 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (318787817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 159393906 + 159393907.

It is an arithmetic number, because the mean of its divisors is an integer number (159393907).

Almost surely, 2^318787813 is an apocalyptic number.

It is an amenable number.

318787813 is a deficient number, since it is larger than the sum of its proper divisors (1).

318787813 is an equidigital number, since it uses as much as digits as its factorization.

318787813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 225792, while the sum is 46.

The square root of 318787813 is about 17854.6300157690. The cubic root of 318787813 is about 683.1256147281.

It can be divided in two parts, 318787 and 813, that added together give a triangular number (319600 = T₇₉₉).

The spelling of 318787813 in words is "three hundred eighteen million, seven hundred eighty-seven thousand, eight hundred thirteen".