318691 has 2 divisors, whose sum is σ = 318692. Its totient is φ = 318690.

The previous prime is 318683. The next prime is 318701. The reversal of 318691 is 196813.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 318691 - 2³ = 318683 is a prime.

318691 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (318601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 159345 + 159346.

It is an arithmetic number, because the mean of its divisors is an integer number (159346).

2³¹⁸⁶⁹¹ is an apocalyptic number.

318691 is a deficient number, since it is larger than the sum of its proper divisors (1).

318691 is an equidigital number, since it uses as much as digits as its factorization.

318691 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 318691 is about 564.5272358354. The cubic root of 318691 is about 68.3056454686.

The spelling of 318691 in words is "three hundred eighteen thousand, six hundred ninety-one".