318821656457 has 2 divisors, whose sum is σ = 318821656458. Its totient is φ = 318821656456.

The previous prime is 318821656429. The next prime is 318821656463. The reversal of 318821656457 is 754656128813.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 300721721161 + 18099935296 = 548381^2 + 134536^2 .

It is a cyclic number.

It is not a de Polignac number, because 318821656457 - 2⁸ = 318821656201 is a prime.

It is not a weakly prime, because it can be changed into another prime (318821656487) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 159410828228 + 159410828229.

It is an arithmetic number, because the mean of its divisors is an integer number (159410828229).

Almost surely, 2^318821656457 is an apocalyptic number.

It is an amenable number.

318821656457 is a deficient number, since it is larger than the sum of its proper divisors (1).

318821656457 is an equidigital number, since it uses as much as digits as its factorization.

318821656457 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9676800, while the sum is 56.

The spelling of 318821656457 in words is "three hundred eighteen billion, eight hundred twenty-one million, six hundred fifty-six thousand, four hundred fifty-seven".