20640050789 has 2 divisors, whose sum is σ = 20640050790. Its totient is φ = 20640050788.

The previous prime is 20640050741. The next prime is 20640050791. The reversal of 20640050789 is 98705004602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13172152900 + 7467897889 = 114770^2 + 86417^2 .

It is a cyclic number.

It is not a de Polignac number, because 20640050789 - 2⁸ = 20640050533 is a prime.

Together with 20640050791, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20640050089) 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, 10320025394 + 10320025395.

It is an arithmetic number, because the mean of its divisors is an integer number (10320025395).

Almost surely, 2^20640050789 is an apocalyptic number.

It is an amenable number.

20640050789 is a deficient number, since it is larger than the sum of its proper divisors (1).

20640050789 is an equidigital number, since it uses as much as digits as its factorization.

20640050789 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 120960, while the sum is 41.

The spelling of 20640050789 in words is "twenty billion, six hundred forty million, fifty thousand, seven hundred eighty-nine".