21202212111121 has 16 divisors (see below), whose sum is σ = 22481599524048. Its totient is φ = 19926415872000.

The previous prime is 21202212111097. The next prime is 21202212111127. The reversal of 21202212111121 is 12111121220212.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 4341538980496 + 16860673130625 = 2083636^2 + 4106175^2 .

It is a cyclic number.

It is not a de Polignac number, because 21202212111121 - 2²¹ = 21202210013969 is a prime.

It is a super-3 number, since 3×21202212111121³ (a number of 41 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21202212111127) 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, 50307571 + ... + 50727271.

It is an arithmetic number, because the mean of its divisors is an integer number (1405099970253).

Almost surely, 2^{21202212111121} is an apocalyptic number.

It is an amenable number.

21202212111121 is a deficient number, since it is larger than the sum of its proper divisors (1279387412927).

21202212111121 is a wasteful number, since it uses less digits than its factorization.

21202212111121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 423972.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 21202212111121 its reverse (12111121220212), we get a palindrome (33313333331333).

The spelling of 21202212111121 in words is "twenty-one trillion, two hundred two billion, two hundred twelve million, one hundred eleven thousand, one hundred twenty-one".