21311201311 has 2 divisors, whose sum is σ = 21311201312. Its totient is φ = 21311201310.

The previous prime is 21311201297. The next prime is 21311201341. The reversal of 21311201311 is 11310211312.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21311201311 - 2²⁹ = 20774330399 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21311201341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10655600655 + 10655600656.

It is an arithmetic number, because the mean of its divisors is an integer number (10655600656).

Almost surely, 2^21311201311 is an apocalyptic number.

21311201311 is a deficient number, since it is larger than the sum of its proper divisors (1).

21311201311 is an equidigital number, since it uses as much as digits as its factorization.

21311201311 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36, while the sum is 16.

Adding to 21311201311 its reverse (11310211312), we get a palindrome (32621412623).

The spelling of 21311201311 in words is "twenty-one billion, three hundred eleven million, two hundred one thousand, three hundred eleven".