20009979089 has 2 divisors, whose sum is σ = 20009979090. Its totient is φ = 20009979088.

The previous prime is 20009979083. The next prime is 20009979097. The reversal of 20009979089 is 98097990002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15122850625 + 4887128464 = 122975^2 + 69908^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20009979089 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20009979089.

It is not a weakly prime, because it can be changed into another prime (20009979083) 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, 10004989544 + 10004989545.

It is an arithmetic number, because the mean of its divisors is an integer number (10004989545).

Almost surely, 2^20009979089 is an apocalyptic number.

It is an amenable number.

20009979089 is a deficient number, since it is larger than the sum of its proper divisors (1).

20009979089 is an equidigital number, since it uses as much as digits as its factorization.

20009979089 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 734832, while the sum is 53.

The spelling of 20009979089 in words is "twenty billion, nine million, nine hundred seventy-nine thousand, eighty-nine".