21202311311 has 12 divisors (see below), whose sum is σ = 22528131552. Its totient is φ = 19950455808.

The previous prime is 21202311233. The next prime is 21202311323. The reversal of 21202311311 is 11311320212.

It is not a de Polignac number, because 21202311311 - 2¹⁰ = 21202310287 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21202311311.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21202313311) 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 in 11 ways as a sum of consecutive naturals, for example, 2409626 + ... + 2418408.

It is an arithmetic number, because the mean of its divisors is an integer number (1877344296).

Almost surely, 2^21202311311 is an apocalyptic number.

21202311311 is a deficient number, since it is larger than the sum of its proper divisors (1325820241).

21202311311 is an equidigital number, since it uses as much as digits as its factorization.

21202311311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17170 (or 17153 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 21202311311 its reverse (11311320212), we get a palindrome (32513631523).

The spelling of 21202311311 in words is "twenty-one billion, two hundred two million, three hundred eleven thousand, three hundred eleven".