21012333215 has 32 divisors (see below), whose sum is σ = 26594061696. Its totient is φ = 15906908160.

The previous prime is 21012333197. The next prime is 21012333227. The reversal of 21012333215 is 51233321012.

It is not a de Polignac number, because 21012333215 - 2¹⁸ = 21012071071 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4929185 + ... + 4933445.

It is an arithmetic number, because the mean of its divisors is an integer number (831064428).

Almost surely, 2^21012333215 is an apocalyptic number.

21012333215 is a deficient number, since it is larger than the sum of its proper divisors (5581728481).

21012333215 is a wasteful number, since it uses less digits than its factorization.

21012333215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4739.

The product of its (nonzero) digits is 1080, while the sum is 23.

Adding to 21012333215 its reverse (51233321012), we get a palindrome (72245654227).

The spelling of 21012333215 in words is "twenty-one billion, twelve million, three hundred thirty-three thousand, two hundred fifteen".