315865261 has 2 divisors, whose sum is σ = 315865262. Its totient is φ = 315865260.

The previous prime is 315865247. The next prime is 315865283. The reversal of 315865261 is 162568513.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 240436036 + 75429225 = 15506^2 + 8685^2 .

It is an emirp because it is prime and its reverse (162568513) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 315865261 - 2⁷ = 315865133 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 315865261.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (315865201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 157932630 + 157932631.

It is an arithmetic number, because the mean of its divisors is an integer number (157932631).

Almost surely, 2^315865261 is an apocalyptic number.

It is an amenable number.

315865261 is a deficient number, since it is larger than the sum of its proper divisors (1).

315865261 is an equidigital number, since it uses as much as digits as its factorization.

315865261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 43200, while the sum is 37.

The square root of 315865261 is about 17772.5986000922. The cubic root of 315865261 is about 681.0316383906.

The spelling of 315865261 in words is "three hundred fifteen million, eight hundred sixty-five thousand, two hundred sixty-one".