318391121 has 2 divisors, whose sum is σ = 318391122. Its totient is φ = 318391120.

The previous prime is 318391067. The next prime is 318391123. The reversal of 318391121 is 121193813.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 293779600 + 24611521 = 17140^2 + 4961^2 .

It is a cyclic number.

It is not a de Polignac number, because 318391121 - 2¹⁸ = 318128977 is a prime.

Together with 318391123, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (318391123) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 159195560 + 159195561.

It is an arithmetic number, because the mean of its divisors is an integer number (159195561).

Almost surely, 2^318391121 is an apocalyptic number.

It is an amenable number.

318391121 is a deficient number, since it is larger than the sum of its proper divisors (1).

318391121 is an equidigital number, since it uses as much as digits as its factorization.

318391121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1296, while the sum is 29.

The square root of 318391121 is about 17843.5176184518. The cubic root of 318391121 is about 682.8421420045.

The spelling of 318391121 in words is "three hundred eighteen million, three hundred ninety-one thousand, one hundred twenty-one".