345969509 has 2 divisors, whose sum is σ = 345969510. Its totient is φ = 345969508.

The previous prime is 345969493. The next prime is 345969511. The reversal of 345969509 is 905969543.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 228312100 + 117657409 = 15110^2 + 10847^2 .

It is an emirp because it is prime and its reverse (905969543) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 345969509 - 2⁴ = 345969493 is a prime.

It is a Sophie Germain prime.

Together with 345969511, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (345969599) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 172984754 + 172984755.

It is an arithmetic number, because the mean of its divisors is an integer number (172984755).

Almost surely, 2^345969509 is an apocalyptic number.

It is an amenable number.

345969509 is a deficient number, since it is larger than the sum of its proper divisors (1).

345969509 is an equidigital number, since it uses as much as digits as its factorization.

345969509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1312200, while the sum is 50.

The square root of 345969509 is about 18600.2556165231. The cubic root of 345969509 is about 702.0142724565.

The spelling of 345969509 in words is "three hundred forty-five million, nine hundred sixty-nine thousand, five hundred nine".