315879521 has 2 divisors, whose sum is σ = 315879522. Its totient is φ = 315879520.

The previous prime is 315879517. The next prime is 315879547. The reversal of 315879521 is 125978513.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 290225296 + 25654225 = 17036^2 + 5065^2 .

It is a cyclic number.

It is not a de Polignac number, because 315879521 - 2² = 315879517 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (315879511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 157939760 + 157939761.

It is an arithmetic number, because the mean of its divisors is an integer number (157939761).

Almost surely, 2^315879521 is an apocalyptic number.

It is an amenable number.

315879521 is a deficient number, since it is larger than the sum of its proper divisors (1).

315879521 is an equidigital number, since it uses as much as digits as its factorization.

315879521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 75600, while the sum is 41.

The square root of 315879521 is about 17772.9997749395. Note that the first 3 decimals coincide. The cubic root of 315879521 is about 681.0418868163.

The spelling of 315879521 in words is "three hundred fifteen million, eight hundred seventy-nine thousand, five hundred twenty-one".