121221012221 has 4 divisors (see below), whose sum is σ = 121249586112. Its totient is φ = 121192438332.

The previous prime is 121221012217. The next prime is 121221012233. The reversal of 121221012221 is 122210122121.

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 121221012221 - 2² = 121221012217 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 121221012221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121221014221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14280581 + ... + 14289066.

It is an arithmetic number, because the mean of its divisors is an integer number (30312396528).

Almost surely, 2^121221012221 is an apocalyptic number.

It is an amenable number.

121221012221 is a deficient number, since it is larger than the sum of its proper divisors (28573891).

121221012221 is an equidigital number, since it uses as much as digits as its factorization.

121221012221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28573890.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 121221012221 its reverse (122210122121), we get a palindrome (243431134342).

The spelling of 121221012221 in words is "one hundred twenty-one billion, two hundred twenty-one million, twelve thousand, two hundred twenty-one".