121020121221 has 4 divisors (see below), whose sum is σ = 161360161632. Its totient is φ = 80680080812.

The previous prime is 121020121151. The next prime is 121020121319. The reversal of 121020121221 is 122121020121.

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: 122121020121 = 3 ⋅40707006707.

It is a cyclic number.

It is not a de Polignac number, because 121020121221 - 2⁹ = 121020120709 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 121020121221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121020125221) 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, 20170020201 + ... + 20170020206.

It is an arithmetic number, because the mean of its divisors is an integer number (40340040408).

Almost surely, 2^121020121221 is an apocalyptic number.

It is an amenable number.

121020121221 is a deficient number, since it is larger than the sum of its proper divisors (40340040411).

121020121221 is an equidigital number, since it uses as much as digits as its factorization.

121020121221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40340040410.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 121020121221 its reverse (122121020121), we get a palindrome (243141141342).

The spelling of 121020121221 in words is "one hundred twenty-one billion, twenty million, one hundred twenty-one thousand, two hundred twenty-one".