315085621 has 2 divisors, whose sum is σ = 315085622. Its totient is φ = 315085620.

The previous prime is 315085619. The next prime is 315085649. The reversal of 315085621 is 126580513.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 278422596 + 36663025 = 16686^2 + 6055^2 .

It is an emirp because it is prime and its reverse (126580513) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 315085621 - 2¹ = 315085619 is a prime.

Together with 315085619, 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 (315025621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 157542810 + 157542811.

It is an arithmetic number, because the mean of its divisors is an integer number (157542811).

Almost surely, 2^315085621 is an apocalyptic number.

It is an amenable number.

315085621 is a deficient number, since it is larger than the sum of its proper divisors (1).

315085621 is an equidigital number, since it uses as much as digits as its factorization.

315085621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7200, while the sum is 31.

The square root of 315085621 is about 17750.6512838262. The cubic root of 315085621 is about 680.4708539652.

The spelling of 315085621 in words is "three hundred fifteen million, eighty-five thousand, six hundred twenty-one".