21135333 has 4 divisors (see below), whose sum is σ = 28180448. Its totient is φ = 14090220.

The previous prime is 21135329. The next prime is 21135337. The reversal of 21135333 is 33353112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (21135329) and next prime (21135337).

It is not a de Polignac number, because 21135333 - 2² = 21135329 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 (21135337) 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, 3522553 + ... + 3522558.

It is an arithmetic number, because the mean of its divisors is an integer number (7045112).

Almost surely, 2^21135333 is an apocalyptic number.

It is an amenable number.

21135333 is a deficient number, since it is larger than the sum of its proper divisors (7045115).

21135333 is an equidigital number, since it uses as much as digits as its factorization.

21135333 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7045114.

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

The square root of 21135333 is about 4597.3180224996. The cubic root of 21135333 is about 276.4838053925.

Adding to 21135333 its reverse (33353112), we get a palindrome (54488445).

The spelling of 21135333 in words is "twenty-one million, one hundred thirty-five thousand, three hundred thirty-three".