20971056389 has 2 divisors, whose sum is σ = 20971056390. Its totient is φ = 20971056388.

The previous prime is 20971056373. The next prime is 20971056427. The reversal of 20971056389 is 98365017902.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10700247364 + 10270809025 = 103442^2 + 101345^2 .

It is a cyclic number.

It is not a de Polignac number, because 20971056389 - 2⁴ = 20971056373 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20971050389) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10485528194 + 10485528195.

It is an arithmetic number, because the mean of its divisors is an integer number (10485528195).

Almost surely, 2^20971056389 is an apocalyptic number.

It is an amenable number.

20971056389 is a deficient number, since it is larger than the sum of its proper divisors (1).

20971056389 is an equidigital number, since it uses as much as digits as its factorization.

20971056389 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 816480, while the sum is 50.

The spelling of 20971056389 in words is "twenty billion, nine hundred seventy-one million, fifty-six thousand, three hundred eighty-nine".