315725381 has 2 divisors, whose sum is σ = 315725382. Its totient is φ = 315725380.

The previous prime is 315725369. The next prime is 315725383. The reversal of 315725381 is 183527513.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 261113281 + 54612100 = 16159^2 + 7390^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-315725381 is a prime.

It is a super-2 number, since 2×315725381² = 199365032415190322, which contains 22 as substring.

Together with 315725383, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (315725383) 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, 157862690 + 157862691.

It is an arithmetic number, because the mean of its divisors is an integer number (157862691).

Almost surely, 2^315725381 is an apocalyptic number.

It is an amenable number.

315725381 is a deficient number, since it is larger than the sum of its proper divisors (1).

315725381 is an equidigital number, since it uses as much as digits as its factorization.

315725381 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 25200, while the sum is 35.

The square root of 315725381 is about 17768.6628928572. The cubic root of 315725381 is about 680.9310925956.

The spelling of 315725381 in words is "three hundred fifteen million, seven hundred twenty-five thousand, three hundred eighty-one".