319390681 has 2 divisors, whose sum is σ = 319390682. Its totient is φ = 319390680.

The previous prime is 319390661. The next prime is 319390691. The reversal of 319390681 is 186093913.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 245705625 + 73685056 = 15675^2 + 8584^2 .

It is an emirp because it is prime and its reverse (186093913) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 319390681 - 2⁷ = 319390553 is a prime.

It is a super-2 number, since 2×319390681² = 204020814219287522, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (319390661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 159695340 + 159695341.

It is an arithmetic number, because the mean of its divisors is an integer number (159695341).

Almost surely, 2^319390681 is an apocalyptic number.

It is an amenable number.

319390681 is a deficient number, since it is larger than the sum of its proper divisors (1).

319390681 is an equidigital number, since it uses as much as digits as its factorization.

319390681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 34992, while the sum is 40.

The square root of 319390681 is about 17871.5047212035. The cubic root of 319390681 is about 683.5559691502. Note that the first 3 decimals are identical.

The spelling of 319390681 in words is "three hundred nineteen million, three hundred ninety thousand, six hundred eighty-one".