319681 has 2 divisors, whose sum is σ = 319682. Its totient is φ = 319680.

The previous prime is 319679. The next prime is 319687. The reversal of 319681 is 186913.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 172225 + 147456 = 415^2 + 384^2 .

It is a cyclic number.

It is not a de Polignac number, because 319681 - 2¹ = 319679 is a prime.

It is a super-2 number, since 2×319681² = 204391883522, which contains 22 as substring.

Together with 319679, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (319687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 159840 + 159841.

It is an arithmetic number, because the mean of its divisors is an integer number (159841).

2³¹⁹⁶⁸¹ is an apocalyptic number.

It is an amenable number.

319681 is a deficient number, since it is larger than the sum of its proper divisors (1).

319681 is an equidigital number, since it uses as much as digits as its factorization.

319681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1296, while the sum is 28.

The square root of 319681 is about 565.4033958158. The cubic root of 319681 is about 68.3763018801.

It can be divided in two parts, 319 and 681, that added together give a cube (1000 = 10³).

The spelling of 319681 in words is "three hundred nineteen thousand, six hundred eighty-one".