340520209 has 2 divisors, whose sum is σ = 340520210. Its totient is φ = 340520208.

The previous prime is 340520179. The next prime is 340520231. The reversal of 340520209 is 902025043.

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., 193989184 + 146531025 = 13928^2 + 12105^2 .

It is an emirp because it is prime and its reverse (902025043) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 340520209 - 2¹³ = 340512017 is a prime.

It is not a weakly prime, because it can be changed into another prime (340520009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 170260104 + 170260105.

It is an arithmetic number, because the mean of its divisors is an integer number (170260105).

Almost surely, 2^340520209 is an apocalyptic number.

It is an amenable number.

340520209 is a deficient number, since it is larger than the sum of its proper divisors (1).

340520209 is an equidigital number, since it uses as much as digits as its factorization.

340520209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2160, while the sum is 25.

The square root of 340520209 is about 18453.1896700814. The cubic root of 340520209 is about 698.3089855939.

The spelling of 340520209 in words is "three hundred forty million, five hundred twenty thousand, two hundred nine".