315243209 has 2 divisors, whose sum is σ = 315243210. Its totient is φ = 315243208.

The previous prime is 315243179. The next prime is 315243217. The reversal of 315243209 is 902342513.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 281568400 + 33674809 = 16780^2 + 5803^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-315243209 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (315243289) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 157621604 + 157621605.

It is an arithmetic number, because the mean of its divisors is an integer number (157621605).

Almost surely, 2^315243209 is an apocalyptic number.

It is an amenable number.

315243209 is a deficient number, since it is larger than the sum of its proper divisors (1).

315243209 is an equidigital number, since it uses as much as digits as its factorization.

315243209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6480, while the sum is 29.

The square root of 315243209 is about 17755.0896646567. The cubic root of 315243209 is about 680.5842793976.

The spelling of 315243209 in words is "three hundred fifteen million, two hundred forty-three thousand, two hundred nine".