21210120202122 has 16 divisors (see below), whose sum is σ = 47133600449280. Its totient is φ = 7070040067356.

The previous prime is 21210120202121. The next prime is 21210120202127. The reversal of 21210120202122 is 22120202101212.

It is a happy number.

21210120202122 is a `hidden beast` number, since 212 + 10 + 120 + 202 + 122 = 666.

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 = 21210120202095 and 21210120202104.

It is not an unprimeable number, because it can be changed into a prime (21210120202121) 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 7 ways as a sum of consecutive naturals, for example, 196390001818 + ... + 196390001925.

It is an arithmetic number, because the mean of its divisors is an integer number (2945850028080).

Almost surely, 2^{21210120202122} is an apocalyptic number.

21210120202122 is an abundant number, since it is smaller than the sum of its proper divisors (25923480247158).

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

21210120202122 is a wasteful number, since it uses less digits than its factorization.

21210120202122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392780003754 (or 392780003748 counting only the distinct ones).

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

Adding to 21210120202122 its reverse (22120202101212), we get a palindrome (43330322303334).

The spelling of 21210120202122 in words is "twenty-one trillion, two hundred ten billion, one hundred twenty million, two hundred two thousand, one hundred twenty-two".