20711898309 has 16 divisors (see below), whose sum is σ = 29215424000. Its totient is φ = 13015457136.

The previous prime is 20711898307. The next prime is 20711898313. The reversal of 20711898309 is 90389811702.

It is not a de Polignac number, because 20711898309 - 2¹ = 20711898307 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20711898307) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 901639 + ... + 924324.

It is an arithmetic number, because the mean of its divisors is an integer number (1825964000).

Almost surely, 2^20711898309 is an apocalyptic number.

It is an amenable number.

20711898309 is a deficient number, since it is larger than the sum of its proper divisors (8503525691).

20711898309 is a wasteful number, since it uses less digits than its factorization.

20711898309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1826184.

The product of its (nonzero) digits is 217728, while the sum is 48.

The spelling of 20711898309 in words is "twenty billion, seven hundred eleven million, eight hundred ninety-eight thousand, three hundred nine".