315665491 has 2 divisors, whose sum is σ = 315665492. Its totient is φ = 315665490.

The previous prime is 315665473. The next prime is 315665507. The reversal of 315665491 is 194566513.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 315665491 - 2²³ = 307276883 is a prime.

It is not a weakly prime, because it can be changed into another prime (315660491) 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, 157832745 + 157832746.

It is an arithmetic number, because the mean of its divisors is an integer number (157832746).

Almost surely, 2^315665491 is an apocalyptic number.

315665491 is a deficient number, since it is larger than the sum of its proper divisors (1).

315665491 is an equidigital number, since it uses as much as digits as its factorization.

315665491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 97200, while the sum is 40.

The square root of 315665491 is about 17766.9775426210. The cubic root of 315665491 is about 680.8880345622. Note that the first 3 decimals are identical.

The spelling of 315665491 in words is "three hundred fifteen million, six hundred sixty-five thousand, four hundred ninety-one".