21335423133 has 16 divisors (see below), whose sum is σ = 30640839680. Its totient is φ = 13161630384.

The previous prime is 21335423129. The next prime is 21335423149. The reversal of 21335423133 is 33132453312.

It is not a de Polignac number, because 21335423133 - 2² = 21335423129 is a prime.

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 21335423133.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21335423173) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4349941 + ... + 4354842.

It is an arithmetic number, because the mean of its divisors is an integer number (1915052480).

Almost surely, 2^21335423133 is an apocalyptic number.

It is an amenable number.

21335423133 is a deficient number, since it is larger than the sum of its proper divisors (9305416547).

21335423133 is a wasteful number, since it uses less digits than its factorization.

21335423133 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8704848.

The product of its digits is 19440, while the sum is 30.

Adding to 21335423133 its reverse (33132453312), we get a palindrome (54467876445).

The spelling of 21335423133 in words is "twenty-one billion, three hundred thirty-five million, four hundred twenty-three thousand, one hundred thirty-three".