345999221 has 2 divisors, whose sum is σ = 345999222. Its totient is φ = 345999220.

The previous prime is 345999193. The next prime is 345999239. The reversal of 345999221 is 122999543.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 339996721 + 6002500 = 18439^2 + 2450^2 .

It is an emirp because it is prime and its reverse (122999543) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-345999221 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (345999421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 172999610 + 172999611.

It is an arithmetic number, because the mean of its divisors is an integer number (172999611).

Almost surely, 2^345999221 is an apocalyptic number.

It is an amenable number.

345999221 is a deficient number, since it is larger than the sum of its proper divisors (1).

345999221 is an equidigital number, since it uses as much as digits as its factorization.

345999221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 174960, while the sum is 44.

The square root of 345999221 is about 18601.0542980768. The cubic root of 345999221 is about 702.0343683036.

The spelling of 345999221 in words is "three hundred forty-five million, nine hundred ninety-nine thousand, two hundred twenty-one".