21201021022122 has 96 divisors (see below), whose sum is σ = 48342178684800. Its totient is φ = 6705275681664.

The previous prime is 21201021022081. The next prime is 21201021022127. The reversal of 21201021022122 is 22122012010212.

It is a happy number.

21201021022122 is a `hidden beast` number, since 212 + 0 + 1 + 0 + 210 + 221 + 22 = 666.

It is a super-2 number, since 2×21201021022122² (a number of 27 digits) contains 22 as substring.

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

It is a junction number, because it is equal to n+sod(n) for n = 21201021022095 and 21201021022104.

It is not an unprimeable number, because it can be changed into a prime (21201021022127) 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, 87252603 + ... + 87495249.

It is an arithmetic number, because the mean of its divisors is an integer number (503564361300).

Almost surely, 2^{21201021022122} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21201021022122, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24171089342400).

21201021022122 is an abundant number, since it is smaller than the sum of its proper divisors (27141157662678).

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

21201021022122 is a wasteful number, since it uses less digits than its factorization.

21201021022122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 245580 (or 245577 counting only the distinct ones).

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

Adding to 21201021022122 its reverse (22122012010212), we get a palindrome (43323033032334).

The spelling of 21201021022122 in words is "twenty-one trillion, two hundred one billion, twenty-one million, twenty-two thousand, one hundred twenty-two".