21133313111 has 4 divisors (see below), whose sum is σ = 21133803552. Its totient is φ = 21132822672.

The previous prime is 21133313083. The next prime is 21133313137. The reversal of 21133313111 is 11131333112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21133313111 - 2¹⁰ = 21133312087 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 (21133313911) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 173615 + ... + 269088.

It is an arithmetic number, because the mean of its divisors is an integer number (5283450888).

Almost surely, 2^21133313111 is an apocalyptic number.

21133313111 is a deficient number, since it is larger than the sum of its proper divisors (490441).

21133313111 is an equidigital number, since it uses as much as digits as its factorization.

21133313111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 490440.

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

Adding to 21133313111 its reverse (11131333112), we get a palindrome (32264646223).

The spelling of 21133313111 in words is "twenty-one billion, one hundred thirty-three million, three hundred thirteen thousand, one hundred eleven".