195967309 has 2 divisors, whose sum is σ = 195967310. Its totient is φ = 195967308.

The previous prime is 195967301. The next prime is 195967361. The reversal of 195967309 is 903769591.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 184878409 + 11088900 = 13597^2 + 3330^2 .

It is an emirp because it is prime and its reverse (903769591) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 195967309 - 2³ = 195967301 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (195967301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97983654 + 97983655.

It is an arithmetic number, because the mean of its divisors is an integer number (97983655).

Almost surely, 2^195967309 is an apocalyptic number.

It is an amenable number.

195967309 is a deficient number, since it is larger than the sum of its proper divisors (1).

195967309 is an equidigital number, since it uses as much as digits as its factorization.

195967309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 459270, while the sum is 49.

The square root of 195967309 is about 13998.8324155981. The cubic root of 195967309 is about 580.8462764902.

The spelling of 195967309 in words is "one hundred ninety-five million, nine hundred sixty-seven thousand, three hundred nine".