21221310111 has 16 divisors (see below), whose sum is σ = 29811964416. Its totient is φ = 13401042336.

The previous prime is 21221310101. The next prime is 21221310119. The reversal of 21221310111 is 11101312212.

It is not a de Polignac number, because 21221310111 - 2⁵ = 21221310079 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221310119) 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, 1485880 + ... + 1500093.

It is an arithmetic number, because the mean of its divisors is an integer number (1863247776).

Almost surely, 2^21221310111 is an apocalyptic number.

21221310111 is a deficient number, since it is larger than the sum of its proper divisors (8590654305).

21221310111 is a wasteful number, since it uses less digits than its factorization.

21221310111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2986102.

The product of its (nonzero) digits is 24, while the sum is 15.

Adding to 21221310111 its reverse (11101312212), we get a palindrome (32322622323).

The spelling of 21221310111 in words is "twenty-one billion, two hundred twenty-one million, three hundred ten thousand, one hundred eleven".