318727681 has 2 divisors, whose sum is σ = 318727682. Its totient is φ = 318727680.

The previous prime is 318727639. The next prime is 318727691. The reversal of 318727681 is 186727813.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 302203456 + 16524225 = 17384^2 + 4065^2 .

It is a cyclic number.

It is not a de Polignac number, because 318727681 - 2¹⁵ = 318694913 is a prime.

It is a super-2 number, since 2×318727681² = 203174669271275522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (318727691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 159363840 + 159363841.

It is an arithmetic number, because the mean of its divisors is an integer number (159363841).

Almost surely, 2^318727681 is an apocalyptic number.

It is an amenable number.

318727681 is a deficient number, since it is larger than the sum of its proper divisors (1).

318727681 is an equidigital number, since it uses as much as digits as its factorization.

318727681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 112896, while the sum is 43.

The square root of 318727681 is about 17852.9460033911. The cubic root of 318727681 is about 683.0826600408.

The spelling of 318727681 in words is "three hundred eighteen million, seven hundred twenty-seven thousand, six hundred eighty-one".