345515561 has 2 divisors, whose sum is σ = 345515562. Its totient is φ = 345515560.

The previous prime is 345515543. The next prime is 345515563. The reversal of 345515561 is 165515543.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 319301161 + 26214400 = 17869^2 + 5120^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-345515561 is a prime.

Together with 345515563, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (345515563) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 172757780 + 172757781.

It is an arithmetic number, because the mean of its divisors is an integer number (172757781).

Almost surely, 2^345515561 is an apocalyptic number.

It is an amenable number.

345515561 is a deficient number, since it is larger than the sum of its proper divisors (1).

345515561 is an equidigital number, since it uses as much as digits as its factorization.

345515561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 45000, while the sum is 35.

The square root of 345515561 is about 18588.0488755544. The cubic root of 345515561 is about 701.7070994756.

The spelling of 345515561 in words is "three hundred forty-five million, five hundred fifteen thousand, five hundred sixty-one".