21311331311 has 2 divisors, whose sum is σ = 21311331312. Its totient is φ = 21311331310.

The previous prime is 21311331277. The next prime is 21311331319. The reversal of 21311331311 is 11313311312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21311331311 - 2³⁰ = 20237589487 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21311331319) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10655665655 + 10655665656.

It is an arithmetic number, because the mean of its divisors is an integer number (10655665656).

Almost surely, 2^21311331311 is an apocalyptic number.

21311331311 is a deficient number, since it is larger than the sum of its proper divisors (1).

21311331311 is an equidigital number, since it uses as much as digits as its factorization.

21311331311 is an evil number, because the sum of its binary digits is even.

The product of its digits is 162, while the sum is 20.

Adding to 21311331311 its reverse (11313311312), we get a palindrome (32624642623).

The spelling of 21311331311 in words is "twenty-one billion, three hundred eleven million, three hundred thirty-one thousand, three hundred eleven".