21315333 has 8 divisors (see below), whose sum is σ = 30606688. Its totient is φ = 13117104.

The previous prime is 21315289. The next prime is 21315341. The reversal of 21315333 is 33351312.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21315333 - 2⁶ = 21315269 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 (21315353) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 273235 + ... + 273312.

It is an arithmetic number, because the mean of its divisors is an integer number (3825836).

Almost surely, 2^21315333 is an apocalyptic number.

It is an amenable number.

21315333 is a deficient number, since it is larger than the sum of its proper divisors (9291355).

21315333 is a wasteful number, since it uses less digits than its factorization.

21315333 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 546563.

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

The square root of 21315333 is about 4616.8531490616. The cubic root of 21315333 is about 277.2664832029.

Adding to 21315333 its reverse (33351312), we get a palindrome (54666645).

The spelling of 21315333 in words is "twenty-one million, three hundred fifteen thousand, three hundred thirty-three".