20716846861 has 2 divisors, whose sum is σ = 20716846862. Its totient is φ = 20716846860.

The previous prime is 20716846781. The next prime is 20716846889. The reversal of 20716846861 is 16864861702.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11345445225 + 9371401636 = 106515^2 + 96806^2 .

It is a cyclic number.

It is not a de Polignac number, because 20716846861 - 2⁹ = 20716846349 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20716826861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10358423430 + 10358423431.

It is an arithmetic number, because the mean of its divisors is an integer number (10358423431).

Almost surely, 2^20716846861 is an apocalyptic number.

It is an amenable number.

20716846861 is a deficient number, since it is larger than the sum of its proper divisors (1).

20716846861 is an equidigital number, since it uses as much as digits as its factorization.

20716846861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 774144, while the sum is 49.

The spelling of 20716846861 in words is "twenty billion, seven hundred sixteen million, eight hundred forty-six thousand, eight hundred sixty-one".