340660409 has 2 divisors, whose sum is σ = 340660410. Its totient is φ = 340660408.

The previous prime is 340660393. The next prime is 340660423. The reversal of 340660409 is 904066043.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 243204025 + 97456384 = 15595^2 + 9872^2 .

It is an emirp because it is prime and its reverse (904066043) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 340660409 - 2⁴ = 340660393 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is equal to p_18328406 and since 340660409 and 18328406 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (340662409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 170330204 + 170330205.

It is an arithmetic number, because the mean of its divisors is an integer number (170330205).

Almost surely, 2^340660409 is an apocalyptic number.

It is an amenable number.

340660409 is a deficient number, since it is larger than the sum of its proper divisors (1).

340660409 is an equidigital number, since it uses as much as digits as its factorization.

340660409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15552, while the sum is 32.

The square root of 340660409 is about 18456.9880803993. The cubic root of 340660409 is about 698.4048090664.

The spelling of 340660409 in words is "three hundred forty million, six hundred sixty thousand, four hundred nine".