21002120101212 has 24 divisors (see below), whose sum is σ = 49929568544016. Its totient is φ = 6868617894528.

The previous prime is 21002120101187. The next prime is 21002120101219. The reversal of 21002120101212 is 21210102120012.

It is a junction number, because it is equal to n+sod(n) for n = 21002120101191 and 21002120101200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21002120101219) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16511100073 + ... + 16511101344.

It is an arithmetic number, because the mean of its divisors is an integer number (2080398689334).

Almost surely, 2^{21002120101212} is an apocalyptic number.

It is an amenable number.

21002120101212 is an abundant number, since it is smaller than the sum of its proper divisors (28927448442804).

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

21002120101212 is a wasteful number, since it uses less digits than its factorization.

21002120101212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33022201477 (or 33022201475 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21002120101212 its reverse (21210102120012), we get a palindrome (42212222221224).

The spelling of 21002120101212 in words is "twenty-one trillion, two billion, one hundred twenty million, one hundred one thousand, two hundred twelve".