21111112204 has 96 divisors (see below), whose sum is σ = 46080760320. Its totient is φ = 8240044032.

The previous prime is 21111112177. The next prime is 21111112207. The reversal of 21111112204 is 40221111112.

It is not an unprimeable number, because it can be changed into a prime (21111112207) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 14793339 + ... + 14794765.

It is an arithmetic number, because the mean of its divisors is an integer number (480007920).

Almost surely, 2^21111112204 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21111112204, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23040380160).

21111112204 is an abundant number, since it is smaller than the sum of its proper divisors (24969648116).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21111112204 is a wasteful number, since it uses less digits than its factorization.

21111112204 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1967 (or 1965 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21111112204 its reverse (40221111112), we get a palindrome (61332223316).

The spelling of 21111112204 in words is "twenty-one billion, one hundred eleven million, one hundred twelve thousand, two hundred four".