21335133 has 16 divisors (see below), whose sum is σ = 29203200. Its totient is φ = 13848576.

The previous prime is 21335123. The next prime is 21335137. The reversal of 21335133 is 33153312.

It is not a de Polignac number, because 21335133 - 2⁴ = 21335117 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21335137) 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, 47293 + ... + 47741.

It is an arithmetic number, because the mean of its divisors is an integer number (1825200).

Almost surely, 2^21335133 is an apocalyptic number.

It is an amenable number.

21335133 is a deficient number, since it is larger than the sum of its proper divisors (7868067).

21335133 is a wasteful number, since it uses less digits than its factorization.

21335133 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 836.

The product of its digits is 810, while the sum is 21.

The square root of 21335133 is about 4618.9969690399. The cubic root of 21335133 is about 277.3523083908.

Adding to 21335133 its reverse (33153312), we get a palindrome (54488445).

The spelling of 21335133 in words is "twenty-one million, three hundred thirty-five thousand, one hundred thirty-three".