21220122122100 has 324 divisors, whose sum is σ = 73155363759660. Its totient is φ = 5141055744000.

The previous prime is 21220122122071. The next prime is 21220122122119. The reversal of 21220122122100 is 122122102212.

It is a happy number.

21220122122100 is a `hidden beast` number, since 2 + 1 + 220 + 1 + 221 + 221 + 0 + 0 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 1580139505296 + 19639982616804 = 1257036^2 + 4431702^2 .

It is a super-3 number, since 3×21220122122100³ (a number of 41 digits) contains 333 as substring.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 176466796 + ... + 176587004.

Almost surely, 2^{21220122122100} is an apocalyptic number.

21220122122100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21220122122100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36577681879830).

21220122122100 is an abundant number, since it is smaller than the sum of its proper divisors (51935241637560).

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

21220122122100 is a wasteful number, since it uses less digits than its factorization.

21220122122100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121872 (or 121851 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 21220122122100 its reverse (122122102212), we get a palindrome (21342244224312).

The spelling of 21220122122100 in words is "twenty-one trillion, two hundred twenty billion, one hundred twenty-two million, one hundred twenty-two thousand, one hundred".