197315309 has 2 divisors, whose sum is σ = 197315310. Its totient is φ = 197315308.

The previous prime is 197315303. The next prime is 197315357. The reversal of 197315309 is 903513791.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 196981225 + 334084 = 14035^2 + 578^2 .

It is an emirp because it is prime and its reverse (903513791) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 197315309 - 2²⁴ = 180538093 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (197315303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98657654 + 98657655.

It is an arithmetic number, because the mean of its divisors is an integer number (98657655).

Almost surely, 2^197315309 is an apocalyptic number.

It is an amenable number.

197315309 is a deficient number, since it is larger than the sum of its proper divisors (1).

197315309 is an equidigital number, since it uses as much as digits as its factorization.

197315309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25515, while the sum is 38.

The square root of 197315309 is about 14046.8967747328. The cubic root of 197315309 is about 582.1750564755.

The spelling of 197315309 in words is "one hundred ninety-seven million, three hundred fifteen thousand, three hundred nine".