21133221311 has 4 divisors (see below), whose sum is σ = 21479667624. Its totient is φ = 20786775000.

The previous prime is 21133221253. The next prime is 21133221337. The reversal of 21133221311 is 11312233112.

It is a happy number.

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 21133221311 - 2⁶ = 21133221247 is a prime.

It is a super-2 number, since 2×21133221311² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21133221211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 173223065 + ... + 173223186.

It is an arithmetic number, because the mean of its divisors is an integer number (5369916906).

Almost surely, 2^21133221311 is an apocalyptic number.

21133221311 is a deficient number, since it is larger than the sum of its proper divisors (346446313).

21133221311 is an equidigital number, since it uses as much as digits as its factorization.

21133221311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 346446312.

The product of its digits is 216, while the sum is 20.

Adding to 21133221311 its reverse (11312233112), we get a palindrome (32445454423).

The spelling of 21133221311 in words is "twenty-one billion, one hundred thirty-three million, two hundred twenty-one thousand, three hundred eleven".