342721409 has 2 divisors, whose sum is σ = 342721410. Its totient is φ = 342721408.

The previous prime is 342721361. The next prime is 342721427. The reversal of 342721409 is 904127243.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 295840000 + 46881409 = 17200^2 + 6847^2 .

It is an emirp because it is prime and its reverse (904127243) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 342721409 - 2⁸ = 342721153 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (342721499) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 171360704 + 171360705.

It is an arithmetic number, because the mean of its divisors is an integer number (171360705).

Almost surely, 2^342721409 is an apocalyptic number.

It is an amenable number.

342721409 is a deficient number, since it is larger than the sum of its proper divisors (1).

342721409 is an equidigital number, since it uses as much as digits as its factorization.

342721409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12096, while the sum is 32.

The square root of 342721409 is about 18512.7363995710. The cubic root of 342721409 is about 699.8104309798.

The spelling of 342721409 in words is "three hundred forty-two million, seven hundred twenty-one thousand, four hundred nine".