21112201111 has 12 divisors (see below), whose sum is σ = 22510603080. Its totient is φ = 19796366720.

The previous prime is 21112201087. The next prime is 21112201133. The reversal of 21112201111 is 11110221112.

It is a happy number.

It is not a de Polignac number, because 21112201111 - 2⁵ = 21112201079 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21112201091 and 21112201100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112201141) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 58045 + ... + 213526.

It is an arithmetic number, because the mean of its divisors is an integer number (1875883590).

Almost surely, 2^21112201111 is an apocalyptic number.

21112201111 is a deficient number, since it is larger than the sum of its proper divisors (1398401969).

21112201111 is a wasteful number, since it uses less digits than its factorization.

21112201111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 271874 (or 271857 counting only the distinct ones).

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

Adding to 21112201111 its reverse (11110221112), we get a palindrome (32222422223).

The spelling of 21112201111 in words is "twenty-one billion, one hundred twelve million, two hundred one thousand, one hundred eleven".