21112221108 has 96 divisors (see below), whose sum is σ = 57152471040. Its totient is φ = 5998371840.

The previous prime is 21112221101. The next prime is 21112221131. The reversal of 21112221108 is 80112221112.

It is a super-2 number, since 2×21112221108² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112221101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 199885 + ... + 286667.

It is an arithmetic number, because the mean of its divisors is an integer number (595338240).

Almost surely, 2^21112221108 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 21112221108, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28576235520).

21112221108 is an abundant number, since it is smaller than the sum of its proper divisors (36040249932).

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

21112221108 is a wasteful number, since it uses less digits than its factorization.

21112221108 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86917 (or 86915 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 21.

The spelling of 21112221108 in words is "twenty-one billion, one hundred twelve million, two hundred twenty-one thousand, one hundred eight".