121220122221021 has 4 divisors (see below), whose sum is σ = 161626829628032. Its totient is φ = 80813414814012.

The previous prime is 121220122220921. The next prime is 121220122221031. The reversal of 121220122221021 is 120122221022121.

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 not a de Polignac number, because 121220122221021 - 2²⁷ = 121219988003293 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121220122221031) 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, 20203353703501 + ... + 20203353703506.

It is an arithmetic number, because the mean of its divisors is an integer number (40406707407008).

Almost surely, 2^{121220122221021} is an apocalyptic number.

It is an amenable number.

121220122221021 is a deficient number, since it is larger than the sum of its proper divisors (40406707407011).

121220122221021 is an equidigital number, since it uses as much as digits as its factorization.

121220122221021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40406707407010.

The product of its (nonzero) digits is 256, while the sum is 21.

Adding to 121220122221021 its reverse (120122221022121), we get a palindrome (241342343243142).

The spelling of 121220122221021 in words is "one hundred twenty-one trillion, two hundred twenty billion, one hundred twenty-two million, two hundred twenty-one thousand, twenty-one".