21011230711 has 2 divisors, whose sum is σ = 21011230712. Its totient is φ = 21011230710.

The previous prime is 21011230697. The next prime is 21011230741. The reversal of 21011230711 is 11703211012.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21011230711 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21011230741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505615355 + 10505615356.

It is an arithmetic number, because the mean of its divisors is an integer number (10505615356).

Almost surely, 2^21011230711 is an apocalyptic number.

21011230711 is a deficient number, since it is larger than the sum of its proper divisors (1).

21011230711 is an equidigital number, since it uses as much as digits as its factorization.

21011230711 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 84, while the sum is 19.

Adding to 21011230711 its reverse (11703211012), we get a palindrome (32714441723).

The spelling of 21011230711 in words is "twenty-one billion, eleven million, two hundred thirty thousand, seven hundred eleven".