221201112012121 has 4 divisors (see below), whose sum is σ = 221344469830912. Its totient is φ = 221057754193332.

The previous prime is 221201112012079. The next prime is 221201112012161. The reversal of 221201112012121 is 121210211102122.

It is a happy number.

221201112012121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221201112012121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221201112012161) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 71678907081 + ... + 71678910166.

It is an arithmetic number, because the mean of its divisors is an integer number (55336117457728).

Almost surely, 2^{221201112012121} is an apocalyptic number.

It is an amenable number.

221201112012121 is a deficient number, since it is larger than the sum of its proper divisors (143357818791).

221201112012121 is a wasteful number, since it uses less digits than its factorization.

221201112012121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143357818790.

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

Adding to 221201112012121 its reverse (121210211102122), we get a palindrome (342411323114243).

Subtracting from 221201112012121 its reverse (121210211102122), we obtain a palindrome (99990900909999).

The spelling of 221201112012121 in words is "two hundred twenty-one trillion, two hundred one billion, one hundred twelve million, twelve thousand, one hundred twenty-one".