345456509 has 2 divisors, whose sum is σ = 345456510. Its totient is φ = 345456508.

The previous prime is 345456487. The next prime is 345456511. The reversal of 345456509 is 905654543.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 341436484 + 4020025 = 18478^2 + 2005^2 .

It is a cyclic number.

It is not a de Polignac number, because 345456509 - 2⁸ = 345456253 is a prime.

It is a super-2 number, since 2×345456509² = 238680399220934162, which contains 22 as substring.

Together with 345456511, it forms a pair of twin primes.

It is a Chen prime.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (345456569) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 172728254 + 172728255.

It is an arithmetic number, because the mean of its divisors is an integer number (172728255).

Almost surely, 2^345456509 is an apocalyptic number.

It is an amenable number.

345456509 is a deficient number, since it is larger than the sum of its proper divisors (1).

345456509 is an equidigital number, since it uses as much as digits as its factorization.

345456509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 324000, while the sum is 41.

The square root of 345456509 is about 18586.4603676978. The cubic root of 345456509 is about 701.6671209881.

The spelling of 345456509 in words is "three hundred forty-five million, four hundred fifty-six thousand, five hundred nine".