21011100111311 has 2 divisors, whose sum is σ = 21011100111312. Its totient is φ = 21011100111310.

The previous prime is 21011100111289. The next prime is 21011100111319. The reversal of 21011100111311 is 11311100111012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21011100111311 - 2⁶ = 21011100111247 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21011100111319) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505550055655 + 10505550055656.

It is an arithmetic number, because the mean of its divisors is an integer number (10505550055656).

Almost surely, 2^{21011100111311} is an apocalyptic number.

21011100111311 is a deficient number, since it is larger than the sum of its proper divisors (1).

21011100111311 is an equidigital number, since it uses as much as digits as its factorization.

21011100111311 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6, while the sum is 14.

Adding to 21011100111311 its reverse (11311100111012), we get a palindrome (32322200222323).

The spelling of 21011100111311 in words is "twenty-one trillion, eleven billion, one hundred million, one hundred eleven thousand, three hundred eleven".