20211309791 has 2 divisors, whose sum is σ = 20211309792. Its totient is φ = 20211309790.

The previous prime is 20211309779. The next prime is 20211309803. The reversal of 20211309791 is 19790311202.

It is a balanced prime because it is at equal distance from previous prime (20211309779) and next prime (20211309803).

It is a cyclic number.

It is not a de Polignac number, because 20211309791 - 2¹⁴ = 20211293407 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20211309191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10105654895 + 10105654896.

It is an arithmetic number, because the mean of its divisors is an integer number (10105654896).

Almost surely, 2^20211309791 is an apocalyptic number.

20211309791 is a deficient number, since it is larger than the sum of its proper divisors (1).

20211309791 is an equidigital number, since it uses as much as digits as its factorization.

20211309791 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6804, while the sum is 35.

The spelling of 20211309791 in words is "twenty billion, two hundred eleven million, three hundred nine thousand, seven hundred ninety-one".