21330021111 has 32 divisors (see below), whose sum is σ = 32634739200. Its totient is φ = 12139231104.

The previous prime is 21330021077. The next prime is 21330021121. The reversal of 21330021111 is 11112003312.

It is a happy number.

It is not a de Polignac number, because 21330021111 - 2¹⁰ = 21330020087 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21330021121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10648036 + ... + 10650038.

It is an arithmetic number, because the mean of its divisors is an integer number (1019835600).

Almost surely, 2^21330021111 is an apocalyptic number.

21330021111 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21330021111 is a deficient number, since it is larger than the sum of its proper divisors (11304718089).

21330021111 is a wasteful number, since it uses less digits than its factorization.

21330021111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3815.

The product of its (nonzero) digits is 36, while the sum is 15.

Adding to 21330021111 its reverse (11112003312), we get a palindrome (32442024423).

The spelling of 21330021111 in words is "twenty-one billion, three hundred thirty million, twenty-one thousand, one hundred eleven".