21203213311 has 6 divisors (see below), whose sum is σ = 24664962480. Its totient is φ = 18174182796.

The previous prime is 21203213261. The next prime is 21203213333. The reversal of 21203213311 is 11331230212.

It is not a de Polignac number, because 21203213311 - 2¹⁷ = 21203082239 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21203213111) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 216359271 + ... + 216359368.

It is an arithmetic number, because the mean of its divisors is an integer number (4110827080).

Almost surely, 2^21203213311 is an apocalyptic number.

21203213311 is a deficient number, since it is larger than the sum of its proper divisors (3461749169).

21203213311 is an equidigital number, since it uses as much as digits as its factorization.

21203213311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 432718653 (or 432718646 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 21203213311 its reverse (11331230212), we get a palindrome (32534443523).

The spelling of 21203213311 in words is "twenty-one billion, two hundred three million, two hundred thirteen thousand, three hundred eleven".