121122222121221 has 4 divisors (see below), whose sum is σ = 161496296161632. Its totient is φ = 80748148080812.

The previous prime is 121122222121217. The next prime is 121122222121297. The reversal of 121122222121221 is 122121222221121.

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 not a de Polignac number, because 121122222121221 - 2² = 121122222121217 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 121122222121191 and 121122222121200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121122232121221) 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, 20187037020201 + ... + 20187037020206.

It is an arithmetic number, because the mean of its divisors is an integer number (40374074040408).

Almost surely, 2^{121122222121221} is an apocalyptic number.

It is an amenable number.

121122222121221 is a deficient number, since it is larger than the sum of its proper divisors (40374074040411).

121122222121221 is an equidigital number, since it uses as much as digits as its factorization.

121122222121221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40374074040410.

The product of its digits is 512, while the sum is 24.

Adding to 121122222121221 its reverse (122121222221121), we get a palindrome (243243444342342).

The spelling of 121122222121221 in words is "one hundred twenty-one trillion, one hundred twenty-two billion, two hundred twenty-two million, one hundred twenty-one thousand, two hundred twenty-one".