21112211010 has 128 divisors (see below), whose sum is σ = 56450628864. Its totient is φ = 5010370560.

The previous prime is 21112210997. The next prime is 21112211011. The reversal of 21112211010 is 1011221112.

It is not an unprimeable number, because it can be changed into a prime (21112211011) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3297132 + ... + 3303528.

It is an arithmetic number, because the mean of its divisors is an integer number (441020538).

Almost surely, 2^21112211010 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21112211010, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28225314432).

21112211010 is an abundant number, since it is smaller than the sum of its proper divisors (35338417854).

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

21112211010 is a wasteful number, since it uses less digits than its factorization.

21112211010 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6628.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21112211010 its reverse (1011221112), we get a palindrome (22123432122).

It can be divided in two parts, 211 and 12211010, that added together give a palindrome (12211221).

The spelling of 21112211010 in words is "twenty-one billion, one hundred twelve million, two hundred eleven thousand, ten".