21321322110 has 96 divisors (see below), whose sum is σ = 60570312192. Its totient is φ = 5160661440.

The previous prime is 21321322109. The next prime is 21321322111. The reversal of 21321322110 is 1122312312.

21321322110 is a `hidden beast` number, since 21 + 321 + 322 + 1 + 1 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (21321322109) and next prime (21321322111).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21321322111) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 623887 + ... + 657173.

It is an arithmetic number, because the mean of its divisors is an integer number (630940752).

Almost surely, 2^21321322110 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21321322110, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30285156096).

21321322110 is an abundant number, since it is smaller than the sum of its proper divisors (39248990082).

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

21321322110 is a wasteful number, since it uses less digits than its factorization.

21321322110 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33958 (or 33955 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 21321322110 its reverse (1122312312), we get a palindrome (22443634422).

The spelling of 21321322110 in words is "twenty-one billion, three hundred twenty-one million, three hundred twenty-two thousand, one hundred ten".