12121010121221 has 16 divisors (see below), whose sum is σ = 12958052336640. Its totient is φ = 11312757603840.

The previous prime is 12121010121193. The next prime is 12121010121229. The reversal of 12121010121221 is 12212101012121.

It is a de Polignac number, because none of the positive numbers 2^k-12121010121221 is a prime.

It is a super-2 number, since 2×12121010121221² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12121010121221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12121010121229) 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, 6802796 + ... + 8397621.

It is an arithmetic number, because the mean of its divisors is an integer number (809878271040).

Almost surely, 2^{12121010121221} is an apocalyptic number.

It is an amenable number.

12121010121221 is a deficient number, since it is larger than the sum of its proper divisors (837042215419).

12121010121221 is a wasteful number, since it uses less digits than its factorization.

12121010121221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15201364.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 12121010121221 its reverse (12212101012121), we get a palindrome (24333111133342).

The spelling of 12121010121221 in words is "twelve trillion, one hundred twenty-one billion, ten million, one hundred twenty-one thousand, two hundred twenty-one".