121221121122121 has 4 divisors (see below), whose sum is σ = 122421330242244. Its totient is φ = 120020912002000.

The previous prime is 121221121122109. The next prime is 121221121122149.

121221121122121 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 73136105361225 + 48085015760896 = 8551965^2 + 6934336^2 .

It is a cyclic number.

It is not a de Polignac number, because 121221121122121 - 2²⁷ = 121220986904393 is a prime.

It is a super-2 number, since 2×121221121122121² (a number of 29 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121221121122092 and 121221121122101.

It is not an unprimeable number, because it can be changed into a prime (121221121122161) 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, 600104559910 + ... + 600104560111.

It is an arithmetic number, because the mean of its divisors is an integer number (30605332560561).

Almost surely, 2^{121221121122121} is an apocalyptic number.

It is an amenable number.

121221121122121 is a deficient number, since it is larger than the sum of its proper divisors (1200209120123).

121221121122121 is a wasteful number, since it uses less digits than its factorization.

121221121122121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1200209120122.

The product of its digits is 128, while the sum is 22.

The spelling of 121221121122121 in words is "one hundred twenty-one trillion, two hundred twenty-one billion, one hundred twenty-one million, one hundred twenty-two thousand, one hundred twenty-one".