340778909 has 2 divisors, whose sum is σ = 340778910. Its totient is φ = 340778908.

The previous prime is 340778873. The next prime is 340778929. The reversal of 340778909 is 909877043.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 243204025 + 97574884 = 15595^2 + 9878^2 .

It is a cyclic number.

It is not a de Polignac number, because 340778909 - 2⁸ = 340778653 is a prime.

It is a super-2 number, since 2×340778909² = 232260529638460562, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (340778929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 170389454 + 170389455.

It is an arithmetic number, because the mean of its divisors is an integer number (170389455).

Almost surely, 2^340778909 is an apocalyptic number.

It is an amenable number.

340778909 is a deficient number, since it is larger than the sum of its proper divisors (1).

340778909 is an equidigital number, since it uses as much as digits as its factorization.

340778909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 381024, while the sum is 47.

The square root of 340778909 is about 18460.1979675192. The cubic root of 340778909 is about 698.4857805884.

The spelling of 340778909 in words is "three hundred forty million, seven hundred seventy-eight thousand, nine hundred nine".