21121332210 has 96 divisors (see below), whose sum is σ = 60457700160. Its totient is φ = 5073321600.

The previous prime is 21121332203. The next prime is 21121332217. The reversal of 21121332210 is 1223312112.

21121332210 is a `hidden beast` number, since 2 + 1 + 121 + 332 + 210 = 666.

It is an interprime number because it is at equal distance from previous prime (21121332203) and next prime (21121332217).

It is a super-2 number, since 2×21121332210² (a number of 21 digits) contains 22 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (21121332217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 10045 + ... + 205775.

It is an arithmetic number, because the mean of its divisors is an integer number (629767710).

Almost surely, 2^21121332210 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21121332210, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30228850080).

21121332210 is an abundant number, since it is smaller than the sum of its proper divisors (39336367950).

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

21121332210 is a wasteful number, since it uses less digits than its factorization.

21121332210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195864 (or 195861 counting only the distinct ones).

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

Adding to 21121332210 its reverse (1223312112), we get a palindrome (22344644322).

The spelling of 21121332210 in words is "twenty-one billion, one hundred twenty-one million, three hundred thirty-two thousand, two hundred ten".