21203313111 has 8 divisors (see below), whose sum is σ = 31412315760. Its totient is φ = 14135542056.

The previous prime is 21203313059. The next prime is 21203313113. The reversal of 21203313111 is 11131330212.

21203313111 is a `hidden beast` number, since 2 + 1 + 20 + 331 + 311 + 1 = 666.

It is not a de Polignac number, because 21203313111 - 2¹⁰ = 21203312087 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21203313113) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 392653920 + ... + 392653973.

It is an arithmetic number, because the mean of its divisors is an integer number (3926539470).

Almost surely, 2^21203313111 is an apocalyptic number.

21203313111 is a deficient number, since it is larger than the sum of its proper divisors (10209002649).

21203313111 is an equidigital number, since it uses as much as digits as its factorization.

21203313111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 785307902 (or 785307896 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

Adding to 21203313111 its reverse (11131330212), we get a palindrome (32334643323).

The spelling of 21203313111 in words is "twenty-one billion, two hundred three million, three hundred thirteen thousand, one hundred eleven".