21221010100111 has 4 divisors (see below), whose sum is σ = 21312087396912. Its totient is φ = 21129932803312.

The previous prime is 21221010100067. The next prime is 21221010100139. The reversal of 21221010100111 is 11100101012212.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21221010100111 - 2⁷ = 21221010099983 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21221010100091 and 21221010100100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221010100711) 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, 45538648051 + ... + 45538648516.

It is an arithmetic number, because the mean of its divisors is an integer number (5328021849228).

Almost surely, 2^{21221010100111} is an apocalyptic number.

21221010100111 is a deficient number, since it is larger than the sum of its proper divisors (91077296801).

21221010100111 is an equidigital number, since it uses as much as digits as its factorization.

21221010100111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91077296800.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 21221010100111 its reverse (11100101012212), we get a palindrome (32321111112323).

The spelling of 21221010100111 in words is "twenty-one trillion, two hundred twenty-one billion, ten million, one hundred thousand, one hundred eleven".