20678234309 has 2 divisors, whose sum is σ = 20678234310. Its totient is φ = 20678234308.

The previous prime is 20678234251. The next prime is 20678234347. The reversal of 20678234309 is 90343287602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13182484225 + 7495750084 = 114815^2 + 86578^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20678234309 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20678234309.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20678234209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10339117154 + 10339117155.

It is an arithmetic number, because the mean of its divisors is an integer number (10339117155).

Almost surely, 2^20678234309 is an apocalyptic number.

It is an amenable number.

20678234309 is a deficient number, since it is larger than the sum of its proper divisors (1).

20678234309 is an equidigital number, since it uses as much as digits as its factorization.

20678234309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 435456, while the sum is 44.

The spelling of 20678234309 in words is "twenty billion, six hundred seventy-eight million, two hundred thirty-four thousand, three hundred nine".