342005309 has 2 divisors, whose sum is σ = 342005310. Its totient is φ = 342005308.

The previous prime is 342005179. The next prime is 342005311. The reversal of 342005309 is 903500243.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 324180025 + 17825284 = 18005^2 + 4222^2 .

It is an emirp because it is prime and its reverse (903500243) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-342005309 is a prime.

It is a Sophie Germain prime.

Together with 342005311, 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 (342005329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 171002654 + 171002655.

It is an arithmetic number, because the mean of its divisors is an integer number (171002655).

Almost surely, 2^342005309 is an apocalyptic number.

It is an amenable number.

342005309 is a deficient number, since it is larger than the sum of its proper divisors (1).

342005309 is an equidigital number, since it uses as much as digits as its factorization.

342005309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3240, while the sum is 26.

The square root of 342005309 is about 18493.3855472707. The cubic root of 342005309 is about 699.3226843006.

The spelling of 342005309 in words is "three hundred forty-two million, five thousand, three hundred nine".