21221202311111 has 16 divisors (see below), whose sum is σ = 23715333684000. Its totient is φ = 18821237529600.

The previous prime is 21221202311051. The next prime is 21221202311137. The reversal of 21221202311111 is 11111320212212.

It is not a de Polignac number, because 21221202311111 - 2⁶ = 21221202311047 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 (21221202311011) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 44950415 + ... + 45420063.

It is an arithmetic number, because the mean of its divisors is an integer number (1482208355250).

Almost surely, 2^{21221202311111} is an apocalyptic number.

21221202311111 is a deficient number, since it is larger than the sum of its proper divisors (2494131372889).

21221202311111 is a wasteful number, since it uses less digits than its factorization.

21221202311111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 569890.

The product of its (nonzero) digits is 96, while the sum is 20.

Adding to 21221202311111 its reverse (11111320212212), we get a palindrome (32332522523323).

The spelling of 21221202311111 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred two million, three hundred eleven thousand, one hundred eleven".