121112111221 has 4 divisors (see below), whose sum is σ = 122645176000. Its totient is φ = 119579046444.

The previous prime is 121112111201. The next prime is 121112111249. The reversal of 121112111221 is 122111211121.

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, and also an emirpimes, since its reverse is a distinct semiprime: 122111211121 = 4831 ⋅25276591.

It is a cyclic number.

It is not a de Polignac number, because 121112111221 - 2¹³ = 121112103029 is a prime.

It is a super-2 number, since 2×121112111221² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121112111195 and 121112111204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121112111201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 766532271 + ... + 766532428.

It is an arithmetic number, because the mean of its divisors is an integer number (30661294000).

Almost surely, 2^121112111221 is an apocalyptic number.

It is an amenable number.

121112111221 is a deficient number, since it is larger than the sum of its proper divisors (1533064779).

121112111221 is an equidigital number, since it uses as much as digits as its factorization.

121112111221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1533064778.

The product of its digits is 16, while the sum is 16.

Adding to 121112111221 its reverse (122111211121), we get a palindrome (243223322342).

The spelling of 121112111221 in words is "one hundred twenty-one billion, one hundred twelve million, one hundred eleven thousand, two hundred twenty-one".