121021111221 has 16 divisors (see below), whose sum is σ = 165128310336. Its totient is φ = 78797650176.

The previous prime is 121021111201. The next prime is 121021111231. The reversal of 121021111221 is 122111120121.

It is a happy number.

It is not a de Polignac number, because 121021111221 - 2⁷ = 121021111093 is a prime.

It is a super-2 number, since 2×121021111221² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 121021111221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121021111201) 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, 1776831 + ... + 1843683.

It is an arithmetic number, because the mean of its divisors is an integer number (10320519396).

Almost surely, 2^121021111221 is an apocalyptic number.

It is an amenable number.

121021111221 is a deficient number, since it is larger than the sum of its proper divisors (44107199115).

121021111221 is a wasteful number, since it uses less digits than its factorization.

121021111221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80932.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 121021111221 its reverse (122111120121), we get a palindrome (243132231342).

The spelling of 121021111221 in words is "one hundred twenty-one billion, twenty-one million, one hundred eleven thousand, two hundred twenty-one".