21202212221121 has 16 divisors (see below), whose sum is σ = 29048331153600. Its totient is φ = 13745836801728.

The previous prime is 21202212221053. The next prime is 21202212221171. The reversal of 21202212221121 is 12112221220212.

It is not a de Polignac number, because 21202212221121 - 2¹⁴ = 21202212204737 is a prime.

It is a super-3 number, since 3×21202212221121³ (a number of 41 digits) contains 333 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21202212221171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 48039786 + ... + 48479123.

It is an arithmetic number, because the mean of its divisors is an integer number (1815520697100).

Almost surely, 2^{21202212221121} is an apocalyptic number.

It is an amenable number.

21202212221121 is a deficient number, since it is larger than the sum of its proper divisors (7846118932479).

21202212221121 is a wasteful number, since it uses less digits than its factorization.

21202212221121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96520928.

The product of its (nonzero) digits is 256, while the sum is 21.

Adding to 21202212221121 its reverse (12112221220212), we get a palindrome (33314433441333).

The spelling of 21202212221121 in words is "twenty-one trillion, two hundred two billion, two hundred twelve million, two hundred twenty-one thousand, one hundred twenty-one".