21002221201121 has 16 divisors (see below), whose sum is σ = 21177116098560. Its totient is φ = 20827978512720.

The previous prime is 21002221201057. The next prime is 21002221201141. The reversal of 21002221201121 is 12110212220012.

It is a cyclic number.

It is not a de Polignac number, because 21002221201121 - 2⁶ = 21002221201057 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21002221201121.

It is not an unprimeable number, because it can be changed into a prime (21002221201141) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1152502616 + ... + 1152520838.

It is an arithmetic number, because the mean of its divisors is an integer number (1323569756160).

Almost surely, 2^{21002221201121} is an apocalyptic number.

It is an amenable number.

21002221201121 is a deficient number, since it is larger than the sum of its proper divisors (174894897439).

21002221201121 is a wasteful number, since it uses less digits than its factorization.

21002221201121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35596.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21002221201121 its reverse (12110212220012), we get a palindrome (33112433421133).

The spelling of 21002221201121 in words is "twenty-one trillion, two billion, two hundred twenty-one million, two hundred one thousand, one hundred twenty-one".