21131079911 has 2 divisors, whose sum is σ = 21131079912. Its totient is φ = 21131079910.

The previous prime is 21131079863. The next prime is 21131079929. The reversal of 21131079911 is 11997013112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21131079911 - 2¹⁸ = 21130817767 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21131039911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10565539955 + 10565539956.

It is an arithmetic number, because the mean of its divisors is an integer number (10565539956).

Almost surely, 2^21131079911 is an apocalyptic number.

21131079911 is a deficient number, since it is larger than the sum of its proper divisors (1).

21131079911 is an equidigital number, since it uses as much as digits as its factorization.

21131079911 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3402, while the sum is 35.

The spelling of 21131079911 in words is "twenty-one billion, one hundred thirty-one million, seventy-nine thousand, nine hundred eleven".